 Since the times of Christopher Columbus, the oceans have played a vital role in international law and for humankind as a whole. The oceans contain innumerable resources and, for example, world trade flows through sea lanes connecting the various continents. The fruit we buy every day at the supermarket, the gasoline that powers our cars, have probably been transported by ship. Therefore, the question of who is entitled to regulate and to exploit the sea is fundamental to these days. For this reason, I chose to study the historical development of the law of the sea, which is the set of rules governing maritime interactions between different nations. I especially focus on the beginning of ocean going navigation and the role that played in this development. As the first Europeans started to sail across the oceans, they felt the need of establishing legal status for the oceans. I believe that the analysis of how the first Europeans dealt with this issue can bring light to today's situation where, in the end, there is still this strong tension between sovereignty and freedom with regard to the oceans. In particular, I analyzed the genesis of these two principles dealing with the oceans. The first is a close sea principle under which it is possible for states to acquire sovereignty possession of the sea. And on the other, the freedom of the seas, which includes the freedom of navigation, the freedom of fishing, and the idea that the sea cannot be possessed by men. The arguing between the supporters of these two opposite views about the oceans later brought a compromise and sort of widely accepted law of the sea. I believe that studying today the arguments used to defend one principle and the other can be still extremely relevant, since, for example, we see that today there is this strong friction between freedom and sovereignty, for example, in the South China Sea or with regard to the Arctic seas to the north of the globe. Thank you.