 Today we're going to continue our discussion of the architecture that resulted from the split between the Eastern and the Roman Empire. And as we mentioned last time, this split was fostered in part because of political difficulties having to do with invasions of various barbarian tribes coming down and threatening Rome and innervating the forces of Rome. And it also had to do with the adoption of Christianity by Constantine, one of the Roman emperors, or at least the legalization of Christianity, after which time Christianity spread very, very quickly. I just want to get to this chart again to show you the split between the East and the West. In the West, Rome remains the capital, but its power base becomes fragmented and it becomes less and less capable of holding together an empire and barely able to rule itself. So pretty much by 476, when the last Roman emperor, Romulus Augustus, hands his crown over to the Odessor, the Western Roman Empire is generally considered to come to a halt. It's kind of interesting if you think about Romulus Augustus, the last Roman emperor, but he has this kind of double name, part of it from the first legendary founder of Rome, Romulus, and the other part of it from Augustus, the founder of the empire. And at this point, he's considered to be so paltry a threat that the barbarian king Odessor doesn't even bother to assassinate him, he just lets him retire quietly to the countryside. Meanwhile, the Eastern Empire, headquartered in Constantinople, becomes stronger and stronger and stronger under powerful rulers like Justinian, for example, who was not only a brilliant warrior, but also one of these rulers who devoted himself to architecture. So under the rule of Justinian, the influence of Byzantine culture and Byzantine architecture spread wide and far. And we see this orange territory here to indicate that domain. Last time we looked at the simplest of early Christian architectural types. This is the Basilica of San Giovanni and Latterano from 313. This is really the first Christian church. And it's strange because you would think, hmm, this is 300 years after Christ. Why did it take so long for Christian churches even to be constructed? Anybody have a take on that? Yes. Exactly. It was taboo. It was against the law. It offered another model of governance and another code of beliefs that threatened the code of beliefs that were authorized by the government. So it was covert. So it was not until the Edict of Milan and not until the legalization of Christianity that the type of Christian church was able to emerge. How would you describe the basic organization of San Giovanni and Latteran, St. John Latteran? What's the plan type? What are the construction principles? What does it have that is similar to Roman architectural precedence? What does it have that seems not to be picking up on the architectural precedence? Yes, sir. Make that into a complete sentence. He said wooden trusses. And wooden trusses are true, but it just depends on the rest of the sentence. See if the sentence is true. Right. In Roman times, it would not have been so common to provide the roofing of a large structure like this with wooden trusses. Why do you think they put wooden trusses here? Yeah, it could be that you really required a lot of engineering know-how to put the big vaults together. And already by this point, the resources and the competencies are becoming diminished so much so that a few hundred years from then, they would have completely forgotten the technologies altogether. I mean, in 330, they could still do vaulting. You had things like the Basilica of Maxentius that were more or less contemporary spectacular vaults. But maybe it's also a modest kind of architecture. If one of the ambitions of the architecture of ancient Rome was to be ostentatious and to demonstrate the glory of the government through these architectural marvels, maybe one of the ambitions of early Christian architecture was, in fact, to be humble, to provide a simple shelter rather than a symbol of glory. Good. What else is characteristic about the early Christian church plan that we see here in St. John Lateran? Yeah? OK, they have, like, colonnades inside. Can you think of another word for the colonnades, this thing that you walk on? Thank you very much. Excellent. Yeah, it has aisles. Do you know what that big thing that the aisles flank is called? Excellent. Yeah, so it has this characteristic plan type of aisles flanking a nave. Yes, is your hand up back there? Excellent. They added a transept to the shape of the Basilica and formed a cross. And you could also proceed that by saying the basic shape was the Basilica, which is a Roman type. But they added a transept to the shape of the Basilica to make it a cross. And in making it a cross, they made it a particularly Christian church. Good. One reason you have all of these aisles here is that the church was full of people not simply attending the Mass, but also visiting various altars on the side. A lot of these churches were burial places for important people, like bishops or cardinals. And so the pilgrims would circulate through the aisles, and they would pay their homage to various characters. So as a point of comparison to this very simple, very humble vaulting of St. John Lateran, I just want to remind you of the vaulting of the Basilica, which are astonishing, really technological wonders, not simply in terms of their shape, but also in terms of their materiality. This is marble. This is gold leaf. This is pulling out all the stops in terms of making an architecture of grandeur and persuasion. And here again, we have old St. Peter's a few years later. It shares similar characteristics with St. John Lateran. It is a modest architecture. It is an architecture that almost turns its back on the structural innovations of Roman architecture in favor of this simple way of working. And if you look at the wall, you see this thin wall with simple punched windows. Quite a different situation than the kind of thick, massive walls you need in order to support the vaultings of something like the Bass of Caracalla. And here, too, we see a bit more of the plan organization. And that is the idea that there's a courtyard in front. And the courtyard has a kind of double purpose. One purpose is that there are assemblies. There are meetings. There are rituals that take place outside. There is a fountain in the middle for ritual cleansings or baptisms. But also it becomes another kind of mask between the church and the city. So it becomes a way, another way of denying the physical importance of the body of the church and maybe celebrating the spiritual importance of the body of the church. A different engagement to what architecture could do than what the Romans had. So early Christian basilicas in Rome that we looked at really characterize what was going on in the Western Empire after the legalization of Christianity. But in the Eastern Empire, a really different kind of development took place. Early Christian churches in Rome were all about procession, all about longitudinal spaces, all about building the symbol of the cross in these Latin cross plans. But when you get to Byzantine architecture, the architecture in Constantine's new capital, Constantinople, present day Istanbul, you begin to get a real predilection for centralized buildings. And a lot of that could have to do with the fact that the rituals, the method that Mass was celebrated, may have been slightly different. And I say may have been because scholars disagree on this. But there is at least one large camp of scholarship that says the celebration of Mass was a kind of secret thing in the Eastern Church, that the congregation didn't worship jointly and in the same space as the celebrants of the Mass, the priests, but they clustered into the aisle spaces at the margins. And so this notion that the center becomes the place where this ritual is observed begins to authorize the idea of strong, centric plans, as opposed to a plan like, say, St. John Lateran, which is all about the procession, and all about a shared space between the priests and the congregation. Maybe not shared in a non-hierarchical way, but shared like we're sharing this space. I'm in the front, you're in the back. You're not hunkering down in the corridors peeking at me. Oh, we haven't read a poem for ages. And this is a good one, because it's about Byzantium. It's a poem by the Irish poet William Butler Yates. And he's looking at this age when an architecture of elaborate detail, an elaborate surface manipulation, an elaborate collectivity in terms of the way workers from all the different disciplines came together to make artifacts. And he's thinking about this as something quite different from the condition that he lived in, where the trades are separated. The architect says one thing. The carpenter does what the architect tells him to do, surrendering some of his autonomy in the process. For Yates, Byzantium seemed like this dream place where all the workers were expressing their own joy in the process and their own contributions. And it became this wonderful collective thing. So let's see what Yates has to say, sailing to Byzantium. Yates is good. Also, Yates is really interested in Celtic revival. He's interested when he's writing this in finding a way for the arts in Ireland to take off in a similar way. So this is not something he's just looking back at nostalgically, but he's invoking the idea of Byzantium as something toward which Ireland of his day might aim. And I just heard on NPR F. Scott Fitzgerald reading poetry. So I'm going to read this as though I were F. Scott Fitzgerald. I think it will be better that way. Oh, sages standing in God's holy fire as in the gold mosaic of a wall. Come from the holy fire, pern in a gyre, and be the singing masters of my soul. Consume my heart away sick with desire and fastened to a dying animal. It knows not what it is. And gather me into the artifice of eternity. Once out of nature, I shall never take my bodily form from any natural thing, but such a form as Grecian goldsmiths make of hammered gold and gold enameling to keep a drowsy emperor awake, or set upon a golden bow to sing of lords and ladies of Byzantium, of what is past and passing and to come. This notion about sick with desire and fastened to a dying animal is a nice expression of how the medieval people viewed the body. We saw in classical thought how the human body is this microcosm of divine order celebrated for its perfection, celebrated for its beauty. And not that Yates is really a medieval guy, but his take on the medieval spirit is that the body becomes this dying animal that the soul is somehow tethered to. And only by pulling yourself out of nature and putting yourself into these eternal creations can you somehow save the situation. We looked at San Vitale as an example of a Byzantine church. This one is in Ravenna. And Ravenna, after Rome had completely collapsed, became the capital of the Western Empire for a brief period of time, 401 to 453. There is a nice collection of these Byzantine buildings there. And just by looking at San Vitale, you can see how typologically different it is from the early Christian architecture of the churches in Rome that we looked at. Here, this is one of those centralized buildings that's somehow being inflected to recognize the idea of procession, to recognize the idea of access, but nonetheless is incredibly emphatic about stipulating where the center is. And if you look at this plan, you might think, my god, this is a bizarre plan because you see this porch or narfex. And you would expect there to be some kind of axial organization going on. And in fact, there are these two little doors, not one door in the middle, but two little doors. And if you come in through the lucky left door, you're on access. If you come in through the unlucky right door, you're off access and in the aisle space. And a lot of that has to do with information we don't see on this drawing, which is to say a courtyard in front of it that's tucked into a dense urban fabric. So this edge aligns with the ideality of a rectilinear courtyard. And these little triangle spaces are kind of like habitable pochets. They're a thick wall that you can pass through. And by passing through these little triangle spaces, you begin to make realignments between the axis of the courtyard, which is out here, and the axis of the church, which is over here. And one reason the axis of the church would have to rotate is that there was a favoring of orientations of east-west in churches. So you wanted to make sure you had the propitious orientation of the church, but you also had to deal with the existing courtyard. We also noticed when we looked at things like San Vitale last time that there's a really different attitude about the wall and a different attitude about how architecture is articulated. And a lot of that has to do with the fact that the wall becomes much, much flatter. The wall becomes this kind of luminous surface upon which sparkling little glass chips have been laid in order to create these beautiful figural ornaments. This is the court of the emperor Justinian under whose patronage San Vitale was constructed. So you look at a wall like this. And again, if you remember the walls of something like the baths of Caracalla, it's altogether different. Caracalla is all about plasticity, all about heaviness, all about the spatial visualization of the wall. And this is all about surface. As though just as the body of the person is somehow being denied and relegated to a lower role, the material body of architecture transforms and becomes much, much more a marker for symbolic meanings. The geometry is important. The ornamental program is important. But the plasticity of the building begins to become undermined. Justinian's best church, and really one of the best churches ever, is the Ayah Sophia in Istanbul, Constantinople. This was built over a church that Constantine had constructed that was burnt down in riots, the Nica riots of I think 530. And so Justinian, in a sense, picking up the mantle of Constantine and challenging Constantine in a fairly direct way by building his church over the ruins of Constantine's church. So that's a tall order. And Justinian is thinking a lot about what it is to build a church in Rome. And what is Rome? And what is Rome in Constantinople? And he has his architects. Isidore of Miletus and Amesia of Thralls build him this thing, which is quite a shocker, given everything we've been looking at before. And I say it's quite a shocker, because it seems as though it's some kind of hybrid, a kind of oscillation between two kinds of conditions. In a sense, it's a basilica. In a sense, it's kind of like the early Christian basilicas. Look, we have a courtyard. We have an axis. We have an apps. We have some aisles. It's exactly what we want in a basilica. But at the same time, it's emphatically centralized. We have a giant dome, a giant dome surmounted by a giant dome. And not only do we have a giant dome, but the dome becomes expansive and linear. So that the thing that reads as the nave, if we think this is a basilica, becomes a serial dome if we think about this as a centralized plan. A completely new structural device is being introduced here that makes it possible to simultaneously have the idea of center and dome and the idea of this extended space. And that device is called the pendentive. The pendentive is just a device to put a circular dome over a square bay. It has to do with the notion of these curving triangles, really, that come down with point loads at the corners of the square. And the curving triangles curve up and a circle is cut around them so that you can then, over these curving things, if you cut a circle out, you put the dome there. So if you look at the plan here, these little curved triangles that you see in plan are actually these curving surfaces called the pendentives that make the transition from square to circle. So that's really great spatially. That's really great spatially because it opens the space up. It's really great spatially also because remember the pantheon dome? We had these ponderous walls. You needed the walls because the loads were coming down all along the edge. And it was tough to make a breach in those walls because you had all this lateral thrust kicking out. You needed a lot of mass. But here, it's really great spatially also because remember the pantheon dome? We had these ponderous walls. You needed the walls because the loads were coming down all along the edge. And it was tough to make a breach in those walls because you had all this lateral thrust kicking out. You needed a lot of mass. But here, perimeter loads have been resolved to point loads, which is pretty smart. And what are you going to do with a lateral thrust? Because you're still getting lateral thrust kicking out. And that too gets dealt with in a sneaky and dematerialized way by displacing the supports from the perimeter to the edges. So these half domes that we have here, right over here, clipping on to the central dome of Agiosophae aqueous bracing. Instead of having massive walls bracing the lateral thrust, we now have domes that take the load. So the thrust is coming down, coming down. And then this double shell that functionally is the aisle of a basilica also becomes a way that pochette, in a sense, gets hollowed out. You have part of the pochette here, part of the pochette here, and a habitable void in between. And that seems crazy. Like, how can you hollow out the pochette and still have a good structure and still have something that's rigid? But you see it all the time. Like, you've seen i-beams, right? The steel beams that are used routinely for construction. They're called i-beams because they look like the letter i. Why are they so wide up on top? And why are they so narrow in the middle? Wouldn't it be better to just have a big hulking beam? No, it wouldn't be. Why is that? Well, weight is certainly one thing. But also, the structural properties have to do, yes, sir. Yeah, absolutely. What I said before about corrugated cardboard is that certain geometries become self-bracing. So in the case of Agia Sophia, these vaulted cells down here become self-bracing. And the geometry of the arch becomes something that works incredibly well as a kind of composite structure to brace the lateral thrust on this side. The pendentives work very successfully as a structural device to dematerialize the building's envelope so that there can be this transparency and permeability of space at the ground plane. They also work very well symbolically. If you look at the plan, you see a square and a circle. That's the diagram we looked at that represented the Vitruvian man. It's the diagram that represents the perfect nesting together between a symbol of the cosmos, the circle, and a symbol of the earth, the square. And in the sense that Agia Sophia is a Christian church, the fact that it is a triangle that acts as the intermediary between the heavens and the earth, the circle and the square is particularly loaded with significance because the triangle is the symbol for the Trinity, the Christian unity of the Father, Son, and Holy Ghost. And so it is the Trinity or the Christian faith that brings together the cosmos and the earth into a happy reconciliation. So this is what the Agia Sophia looks like from a distance. You can see a real direct expression of the interior space on the exterior space. There is this wonderful cascading of domes down from one to the other. And if you look at it in its present condition, it looks a little bit surprising because it's flanked by minarets, these little needle-like things. And that has to do with the fact that, of course, Turkey now is an Islamic country for the most part, and over the centuries it has gone towards serving one faith to serving another. And I think right now it's a public monument, although I'm not 100% sure. So I don't know if these diagrams show you any better how these pendentives are working. Here you can see the curved surface of the pendentive pretty clearly, and here you can see the base upon which the domes springs, where you have this very thin ring of pendentives coming down to this kind of double structure at the perimeter over here. And so a point of comparison that's pretty useful is the Pantheon. Because I think if you're building in Constantinople, the new Rome, and you're building over the ruins of an old church that Constantin put there, you're not simply dealing with Constantin, but you're dealing with the old Rome, too. And so you'll be dealing with the Pantheon if you're dealing with a centralized church. So the Pantheon is fabulous, don't get me wrong, but also kind of stupid. The technique for building the Pantheon dome is not wizardry. It is something that is a fairly straightforward way to make a dome. In many ways, not so different from the dome of the Treasury of Atreus that we saw in Mycenae, where there's a slight displacement of material having to do with compression rings that stack up. And finally, you get a dome. Of course, it's much more elaborated than the Treasury of Atreus, but it's a simple construction. It's not using elaborate ingenuity, as opposed to the Hagia Sophia, which seems to take the ambitions of the Pantheon and then dematerialize the envelope with some kind of spectacular way. We don't have records from antiquity telling us what the ancients thought about their buildings, but we do have a scribe who worked for Justinian, who described the contemporary impression of the Hagia Sophia, a guy called Procopius. And it's pretty great. I'm just going to read a little bit of it. And this is amazing. This is a guy many hundreds of years ago describing the effect of this church. It abounds exceedingly in sunlight and in the reflections of the sun rays from the marble. Indeed, one might say that its interior is not illuminated from without by the sun, but that the radius comes into being within it. Such an abundance of light bays the shrine. The dome is marvelous in its grace, but by reason of seeming insecurity of its composition altogether terrifying. For it seems somehow to float in the air and on no firm basis, but to be poised aloft to the peril of those inside it. And I think that's just a spectacular description of the ability of this architecture to impress in a way that's quite different from the way that the Roman architecture impressed. Roman architecture may be impressed through super abundance of material. Like, wow, how'd they get all this stuff here? The Byzantine architecture, at least the Hagia Sophia, amazes because it seems to defy gravity and it seems to be so thin and so immaterial, yet nonetheless contains this kind of pure disposition of space and light. If you look at the Hagia Sophia on the outside and compare it to the Pantheon, you can see that the typology of, or let's say at least the facade articulation of the Pantheon is not a bit interesting to the people building the Hagia Sophia. And to me, that makes sense. Does anybody have an idea about why that would make sense? Why wouldn't you want your great Christian church to look like the Pantheon? If the Pantheon's such a great church. Right, it's a pagan temple. It's a pagan temple to a whole bunch of pagan gods. A Christian church should look different and so there's no interest whatsoever in reprising the kinds of elements that articulated the facades of pagan churches. And here's, I think, a good view of how these structural systems differ. We noticed when we looked at the walls of the Pantheon that there were these niches carved inside that helped transfer the load and the geometry of which helped brace the structure. And you can see that even so it's quite a thick thing, whereas in the case of the Hagia Sophia, it's incredibly light and incredibly delicate and even more so in Justinian's age. When Procopius was writing this, it was a thinner, less braced thing than it is now. This sometimes happens with great architecture. You build it so closely to the tolerances that it falls down. So the Hagia Sophia has fallen down at least three or four times. Sometimes because of earthquakes and sometimes because they were just too much in the daredevil mode when they constructed it. If you see it now, you will see that there are all kinds of buttresses all around it that are helping to brace the lateral thrust. That this idea was a good idea, but you throw a little bit of earthquake shaking in there. And the best ideas and the most over-designed structures will fall, let alone the Hagia Sophia. So let's look at this interior space that Procopius was talking about. It is pretty amazing, even with all the retrofitting of the buttresses. This slide is a bit too green. It's really golden in color. The little glass tessera. A tessera is a little glass piece of a mosaic. Are luminous and golden. And look at how the dome sits on the pendentives. This is really quite amazing, right? This is the dome. This is the space of the church. You would have to say, a dome is heavy. I've seen the pantheon. How can you have this ring of windows here? How is that possible? What are you doing? God must be powerful to make this thing stand up. I am terrified. But the solution is that the very structure of this dome is quite different than the structure of the pantheon dome. The pantheon dome had to do with the horizontal stacking of rings. The Hagia Sophia dome has to do with ribs. Just as the plan structure uses the pendentives to isolate the loads to points rather than perimeter surfaces, so too is the dome structure organized by all these ribs that come together. So you have lots and lots of little point loads that come down on the pendentives rather than a continuous perimeter wrapper. Look at the modeling of surface. Incredibly different from the way surface was articulated in classical architecture. And again, it's an argument about the plasticity and the engagement with close observation of nature. You look at a Corinthian column capital and there are these little leaves unfurling and sometimes little blossoms, things that seem very graceful, things that are very much cut in relief to allow your hand to move around the space. And here instead, it is pattern making, it is surface making. It's almost as if the column capital is being dealt with as an ornamented surface in the same way that the wall is being dealt with at a luminous ornamented surface rather than something that bears weight. And I think a lot of it does have to do with these very, very different ambitions. The idea that light is created within the church and emanates out is a beautiful observation of what a church could do. And this idea that associates light and divine presence is something that continues through church building symbolism. When the Western empire fragmented, various cities were identified as seats of power. Milan was one, Ravenna was one, Aquileia to the north of Venice was one, and Venice was nothing. Venice was this pathetic little fishing village. Venice was a little bit of high ground and a couple of fishing boats. And actually right now, if you ever go to Venice, you'll see that it's an island. It's not connected to the mainland. It's this thing floating out in the middle of the Adriatic. And it's artificial ground also. In order to build in Venice, you have to get these trees that they bring in from Croatia because they have good trees there and they drive them down. So you get 50 foot long trees and they still do this nowadays. It's kind of amazing. And they have these like methods of hammering these things down so that you build up this new fortified ground plane upon which you can build your buildings. So Venice wanted to become a city of greater prominence. It began to expand. It began to develop an arsenal that built great vessels for sea travel, but also for warfare. Venice became an important port, but it was still nothing as a city. And the reason it was nothing as a city is that it didn't have a Roman past. It didn't have the imprimatur of ancient Rome and it didn't have a major church. It didn't have any great relics. They needed some. They needed to get some relics in order to establish the presence of an important church. This painting by the mannerist painter, Tintoretto, Venetian painter, probably from around 1560, shows you this project, this kind of crusade that the Venetians mounted to go to Alexandria in Egypt, where St. Mark, the apostle, was interred and to go there and steal his body. Okay, and the reason they wanted to steal his body is this is an important relic. This is an apostle. If they could get the body of St. Mark to Venice, then they would be able to establish a church. Then they would be able to attract pilgrims. Then the status of the city would become not simply mercantile, but also important in terms of its presence in the Christian pantheon. So this is the removal of the body of St. Mark. And this painting is quite fabulous. This is mannerist space at its best. Look at the disequilibrium between the left side of the painting and the right side of the painting. The left side of the painting seems to be pushing so far forward toward you that it's almost bursting through the picture plane. And at the same time, the right side of the painting seems to be whooshing back so far and so fast that even the people seem to be flung into the aisles of the colonnade next to them. So there's this disequilibrium of spatial tension and side to side. And the compositional way of representing that I think goes hand in hand with this incredibly powerful task of removing the body of St. Mark and thereby founding a new status for Venice. One more little anecdote about the removal of the body of St. Mark. Who knows if this is true or not, but this is commonly written up in guidebooks to Venice. Okay, one thing to go to Alexandria and have a crusade. Another thing to find the body of St. Mark. Still harder to get the body of St. Mark through customs, which apparently they had during the crusades, which seems crazy. But how are you gonna get out the body of St. Mark? And what they did was pack it in pork. So they took this shriveled old mummy of St. Mark and packed it in a big crate of pork. And when they were going through the controls, the Muslims who were soldiers guarding the boundaries said, what have you got in there? And they said, pork, wanna take a look? And the Muslims said, no, no, no, pork is disgusting. And so they got the pork smeared body of St. Mark out for Venice, and that was a great day for Venice. On the left, we see one of the most important churches in Constantinople, a Justinian church, not really because of its importance, certainly Agia Sophia was the most important church, but because of its form, its typological organization. It gives us one of the first instances of a quincunx, funny word, a quincunx is just a five-domed church. So the basic plan type that we have here at the Church of the Holy Apostles is what kind of cross? Greek, thank you, why do you say Greek? Yeah, because it's like equal. A Greek cross has the arms of the cross more or less equal around the center, as opposed to a Latin cross, which is the kind of cross we saw in the early Christian churches in Rome, which have a long processional nave. So the Greek crosses are centric, and the quincunx in particular has these five domes. And this becomes a highly copied model for what a church under the Eastern Empire might look like, or any Byzantine church. And the type is conserved for a long period of time. We know that the Justinian churches come from around 525-30. This is St. Mark's from the 11th century, more or less reprising the same plan type as the Church of the Holy Apostles. Once again, it's a kind of great looking quincunx with maybe a few transformations, but truly not many. Even the idea of the material surface of the interior that we saw way back in Ravenna and Constantinople in buildings like San Vitale in Ravenna or Agia Sophia in Constantinople, Istanbul, we see here in St. Mark's. And that is this denial of the material presence of surface in favor of the creation of this luminous field of pattern and ornament. And the façade of St. Mark's is pretty amazing because it makes explicit use of spoils. The Venetians have this great arsenal. The Venetians have this great navy. The Venetians are conquering both sides of the Adriatic. The Venetians are conquering Greece. The Venetians are making incursions into Alexandria. The Venetians are conquering Constantinople. The Venetians had a lot of these kind of successful battles, but for the most part, they were authorized crusades because they were going off to the land of people who had not converted to Christianity. But at a certain point, the Venetians got so greedy, they basically raided Istanbul. They raided Constantinople and they took these horses out of one of the fora in Constantinople, this quadrigo, these four bronze horses. And they're now on display right on top of the portico to the St. Mark's Church. And we have all kinds of things. Like, look, here are Constantine's sons. The Venetians got those, too. And lots of columns, not only from Constantinople, but also columns from Greek temples, columns from anybody who wasn't guarding their columns well enough. And they're encrusted on the façade, and they are spoils. And spoils simply mean things that you take away as kind of trophies of your victory over another culture. But really, it was considered to be very bad form to have a crusade against Constantinople just because they had good stuff that you wanted. That seemed really difficult to justify from any kind of religious basis. From the time of Justinian, there's a kind of low, let's say, in terms of great architectural projects until around 800 when Charlemagne comes onto the scene. But it doesn't mean that culture was at a standstill. It just means that the centers of culture and cultural production shifted away from the state and shifted away from the centralized church to monasteries. There was a great kind of flourishing of monastic culture. And the earliest monks were hermit monks. You would be out in the wilderness meditating, not talking to anybody, fasting. But Saint Benedict, in around 530, began to consolidate the monks together and form the Benedictine order. And one of the missions of the Benedictine order was to be the conservators of culture. So a task that the monks would have would be copying manuscripts. You may have seen pictures of these illustrated manuscripts. Or if you've gone into any museums that have these on display, they're really, really beautiful things. They're hand-panned, beautiful calligraphy things, lots of illustration, gold leaf in the margin. So you have the Benedictines creating these centers of learning, these institutions to conserve culture. And at the same time, they're creating this big administrative network from one Benedictine monastery to another Benedictine monastery to another Benedictine monastery so that if anything counts as a kind of organized infrastructure during this period between, say, Justinian and Charlemagne, it is the structure of the monastic order. But let's just kind of look at our little timeline to get us up to Charlemagne. In 312, Constantine legalizes Christianity with the Edict of Milan. Clovis adopts Christianity in 496. Christianity is really becoming solidly established in European territory. In the 7th century, you have the rise of monasticism. These monasteries established by Benedict are flourishing. And not only Benedictine monasteries, but also other sects of monasteries. 610, Muhammad, founds the Islamic religion. So you now begin to have other strong cultural impulses coming into play. And from 610 to 733, there's a large spread of Islam through Arabia, Southern Europe, Africa, Asia, and India. It's extremely effective in terms of moving quickly across a lot of territory. Charles Martel defeats the Arabs at the Battle of Tours. And with this, he stops the spread of Islam. Tours is the south of Paris. So Tours is right in the middle of Europe. That battle was really one of the decisive turning points in keeping Europe in a Christian country and expelling the Arabs to the south. And with that battle, Charles Martel begins to consolidate power, not simply in the area around Île-de-France, the area around Paris, but also he begins to bring together a lot of city states in France and consolidate them together and make a new empire. We talk about Charles as the originator of a period called Carolingian. Charles Martel's son was Pepin, and Pepin's son was Charlemagne. And Charlemagne continued this project of consolidation initiated by Charles Martel and Pepin, and really at a certain point decided to declare himself to be the Holy Roman Emperor. So when we talk to you next time, we'll continue our discussion of Carolingian architecture. And specifically, we'll talk about the imperial palace in Athens.