 In the Hall of Fame of history's greatest conquerors, Alexander the Great is arguably the most notorious. During his reign, Alexander the Great's empire stretched from Greece in the West, all the way to parts of ancient India in the East. Undefeated in battle, Alexander earned such titles as Pharaoh of Egypt, King of Persia and Lord of Asia during his life, he gave his name to more than 20 cities across his empire, including Alexandria in Egypt. Chittered by the famous Greek philosopher Aristotle as a child, Alexander succeeded his father at the age of 20, after King Philip II of Macedonia was assassinated in 336 BC. Alexander went on to rule as King of Macedonia for 13 years until 323 BC. In Alexander's time, the Celts were mainly contained to the northwest of Macedonia, around Alleria and Panonea in the Balkan region, as the strength of Macedonia under Alexander checked the power of numerous groups in the area. Instead of invading the lands of Macedonia and Greece, the Celts sued for peace. In 335 BC, Celtic emissaries from the Adriatic region travelled to the court of Alexander to negotiate a treaty of friendship and hospitality. Some historians argue that the part of the Celts' desire for this meeting was to weigh Alexander's military might. Luckily for us, the Greek historian Strabo documented this meeting, writing that the king received them kingly and asked them when drinking what it was that they most feared, thinking that they would say himself. But they replied that they feared nothing except that the sky might fall on them, although indeed they added they put above everything else the friendship of such a man as he. A second meeting between the Celts and Alexander is recorded in 323 BC by the Greek historian Arian with the meeting taking place in Babylon, modern day Iraq. In the same year however, Alexander died in Babylon. The exact nature of his death is unknown, but he seemed to fall ill after a prolonged banquet and drinking session, dying over a week later. Rumours that he was poisoned have endured to the present day. Regardless of the cause, Alexander's death left a huge power vacuum, which sparked a series of civil wars that tore his empire apart. This weakness was witnessed by every group in the area, including the Celts. In the decades that followed, the Celts became more emboldened, and started venturing into territory previously under the firm control of Alexander the Great. In 298 BC, Symbales led a force of Celts into Macedonia and Thrace, but they were pushed back by the Macedonian king Cassander. In 280 BC, a more successful Celtic campaign took place, when a Celtic and Thracian force led by Balgios invaded south and beheaded the king of Macedonia at the time Ptolemy Seranus. The following year, in 279 BC, a massive horde of Celtic warriors headed south from modern Bulgaria and invaded Greece, under the leaders Brennus and Archechorius, tens of thousands of Celts marched for Greece, motivated by the wealth of the Greek states with their silver and gold coins. I should mention that around this point, when Brennus and Archechorius headed for Greece, another group of Celtic warriors broke off from the main army, and headed for Anatolia, going on to settle what became known as Galatia in modern-day Turkey. After suffering a heavy defeat at the hands of a Macedonian force, Brennus and Archechorius pushed southwards and entered Greece through the Pass of Thermopylae. Brennus spearheaded this assault, outflanking the Greeks, defending Thermopylae. Too impatient to wait for Archechorius' forces to catch up, or even to bury his dead warriors, Brennus headed straight for the spiritual centre of the ancient Greek world, Delphi, home to Pythia, the Oracle and High Priestess at the Temple of Apollo. Exactly what happened at Delphi is not quite clear. Some sources suggest that the Celts pillaged the sacred sites of Delphi and escaped with treasure, including gold and silver that may have ended up back in modern-day Toulouse in France. Other sources suggest that Apollo, the presiding deity, struck the Celts down with thunder and lightning and an earthquake that resulted in fallen rocks decimating the Celtic ranks. This was all compounded by the local Fockean population using guerrilla warfare tactics against the Celts, while disrupting foraging parties looking for food. Regardless of the precise details, the Celts were not in Delphi long. Disheartened, the Celts began to retreat, fuelled by infighting in the ranks and attacks by local forces. Brennus, who had been wounded in battle, went on to commit suicide, either by drinking undiluted wine or by some other drunken means. On their retreat north, through Greece, the Celts were met by local Greek populations, such as the Thessalians, whose sort of revenge for the brutality the Celts had shown on their way south to Delphi. Some sources suggest that not one Celt left Greece safely, although this seems an exaggeration. The Celtic campaign in Greece seemed more of a smashing grab raid for treasure, as opposed to anything more meaningful, and the invasion and retreat probably took place in the same year of 279 BC. The Celts, however, would remain a powerful group in Europe for centuries, albeit outside of Greece. The remaining Celts from the Greek campaign settled in various regions north of Greece, including in modern Serbia, where they became known as the Scordisci. of this channel. Some of these benefits you will gain, including gaining early access to snippets of my upcoming video scripts, greater voting power to participate in Patreon-only channel-related polls, and your name appearing in the credits of my videos. You can also follow Celtic History Decoded on Instagram, TikTok and Twitter. Finally, please tell your friends and family about this channel. Thanks for watching. More videos are coming soon.