States can join together to form communities so they are better able to promote common interests. One such community is the so-called “international legal community”. Its members have undertaken to keep to certain rules in their dealings with one another. These rules are laid down in international law. International law consists of a large number of treaties and is divided into laws governing peace and laws governing war. It describes exactly what rights and obligations nations have in peace and in war. International law centres on the United Nations Charter of 1945 and human rights. All the countries belonging to the international legal community have signed these treaties. The idea of a common law for all peoples is very old. Hugo Grotius (1583-1645) was the first to write about it. That is why he is considered the founder of international law.