Grotius
Hugo Grotius was a Dutch philosopher, lawyer, and diplomat born in 1583. He is often referred to as the "father of international law" for his influential writings on the subject. His most famous work, De Jure Belli ac Pacis (On the Law of War and Peace), laid the groundwork for modern legal principles governing war and peace between nations.
Grotius argued that natural law, derived from reason, should guide human conduct and international relations. His ideas emphasized the importance of treaties and the rights of individuals, influencing later thinkers and shaping the development of international law and human rights.