Ethiopia is one of the oldest independent nations in the world. It has long been an intersection between the civilizations of North Africa, the Middle East and Sub-Saharan Africa. Unique among African countries, Ethiopia was never colonized, maintaining its independence throughout the Scramble for Africa onward, except for a five-year period (1936-41) when it was under Italian military occupation. During this period, the Italians occupied only a few key cities and major routes, and faced continuing native resistance until they were finally defeated during the Second World War by a joint Ethiopian-British alliance. Ethiopia has long been a member of international organizations: it became a member of the League of Nations, signed the Declaration by United Nations in 1942, founded the UN headquarters in Africa, was one of the 51 original members of the UN, and is the headquarters for and one of the founding members of the former OAU and current AU.