Tanzania only came into existence in 1964, following the union of Tanganyika and Zanzibar in 1964. There are over 120 tribes on the mainland, most of which migrated from other parts of Africa.
The first European arrival was the Portuguese explorer, Vasco da Gama who visited the coast in the late 15th century. The Portuguese also controlled Zanzibar until 1699, when they were ousted from the island by Omani Arabs. In the late 19th century, along with Rwanda and Burundi, Tanganyika was absorbed into the colony of German East Africa, as a consequence of a deal between the British and Germans – one process in the European colonial carve-up of Africa.
Tanganyika was a fairly quiet part of the German empire, until the end of World War I. Then following the German defeat, it was administered by the British under successive League of Nations and United Nations mandates. Tanganyika became independent within the Commonwealth in 1961, after a period of self-government during which the principal nationalist party, the Tanganyika African National Union (TANU) emerged as the dominant political force. Its charismatic leader, Julius Nyerere held the post of President from independence to 1985, and in 1992 the constitution was amended to allow multi-party democracy. In 1964, Tanganyika joined with Zanzibar and became Tanzania.