Hugo Grotius (1583 –1645, in Dutch Hugo de Groot) was a Dutch humanist, diplomat, lawyer, theologian, jurist, poet, and playwright.
A teenage intellectual prodigy, he started studying law at Leiden University at the age of 11. Grotius is considered by many as the ‘father of international law’. Hugo Grotius was one of the first to define expressly the idea of one society of states, governed not by force or warfare but by actual laws and mutual agreement to enforce those laws.
Two of his books have had a lasting impact in the field of international law: De Jure Belli Ac Pacis (On the Law of War and Peace) and the Mare Liberum (The Freedom of the Seas).
During a period of truce between Spain and the Netherlands, Grotius was arrested and imprisoned in the castle of Loevestein because he called for a stable peace with Spain (which was against the wishes of governor Maurits of the Netherlands). While imprisoned, he was allowed to study and permitted to write books. To facilitate that, Grotius was regularly sent a coffin-sized bookcase filled with books. This bookcase was brought back and forth by the soldiers who were guarding him. Initially, the bookcase was strictly controlled, but later, the regime relaxed and Grotius was able to escape by hiding in it. He then fled to France. His request to the States of Holland for his wife and children to join him in France was granted on the condition that Grotius would never return to the Netherlands.