Hugo Grotius, also known as Huig de Groot, was a Dutch jurist, theologian, and philosopher who is often considered the father of international law. His seminal work, On the Law of War and Peace, laid the foundations for the principles of just war and international justice. Grotius's ideas on natural law, human rights, and the conduct of nations have had a profound and lasting impact on the development of international law and political philosophy. His legacy continues to influence legal thought worldwide.