Archeological discoveries made in the Laetolil area indicate that humanlike creatures inhabited what is now Tanzania as early as 3,800,000 years ago. Despite these findings, little is known of the development of prehistoric and early historic humans in this area.
During the early Christian Era, Arabia, Persia, India, Greece, and China carried on trade with the coastal regions of eastern Africa, then known as the Land of Zinj. Beginning in the 4th century, Bantus from the south and west began to occupy the coast. Arab settlers came in the 8th century and established the city-states of Kilwa and Pangani; some Persian colonies were established in the 10th.
From the mid-13th century to the end of the 15th, the coastal areas and the offshore islands enjoyed prosperous times. Important trading centers were Kilwa, Pangani, Mafia, and Zanzibar. Gold, ivory, and slaves were exported. Among the traders on the coast the language called Swahili developed from various Bantu dialects. Also during this period, Arab influence and Islamic culture spread among the Bantu-speaking peoples of the coast. In the interior regions, several Bantu kingdoms were being formed.
Early in the 16th century, the Portuguese seized the main port cities and took control of the Indian Ocean trade. Two centuries later, the coastal populations, with the aid of the Arab sultanate of Oman, were able to expel the Portuguese. Many of the cities then fell under the nominal rule of Oman.
In 1840 Seyyid Said, sultan of Oman, made Zanzibar his capital. He introduced the cultivation of cloves and the plantation system. The east African coast gradually was absorbed into the sultanate of Zanzibar. To meet the increasing demand for slaves and ivory, Arab traders began to move into the interior of the mainland to raid and to trade.
European explorers and missionaries penetrated the interior of eastern Africa in the mid-19th century. Notable explorations were made by Richard Burton, John Hanning Speke, and David Livingstone. The main contenders for colonies were Germany, Great Britain, and France. Germany wrested control of what is now mainland Tanzania from the Arabs and made it a part of German East Africa in 1885. Zanzibar was claimed as a protectorate by the British in 1890.
British forces captured German East Africa after a long campaign during World War I. Tanganyika (as the British called it) was officially placed under British control as a League of Nations mandate in 1922; in 1946 it became a United Nations trusteeship, administered by Great Britain.
The Tanganyika African National Union (TANU), a nationalist political party, was founded in 1954 by Julius K. Nyerere. Through TANU's efforts, Tanganyika gained independence in 1961. Zanzibar received independence in 1963. Early in 1964, the Arab-dominated government of Zanzibar was overthrown. The new African nationalist leaders sought union with Tanganyika. In April, 1964, the two countries were merged as the United Republic of Tanganyika and Zanzibar, with Nyerere, the president of Tanganyika, becoming president. The nation, renamed Tanzania in October, 1964, became a member of the British Commonwealth.
Nyerere adopted a program of socialism in an attempt to make the nation self-sufficient. Banks, insurance companies, and manufacturing concerns were nationalized in the early 1970's, and in the middle of the decade most of the rural population was organized into ujamaa (collective) villages.
In 1985, Ali Hassam Mwinyi, selected by Nyerere as his successor, was elected president. Nyerere retained his position as leader of the party until 1990, when he resigned. Ten people were killed in the Tanzanian capital in 1998 by a terrorist bombing of the U.S. embassy. After the bombing, Tanzania developed a closer relationship with the United States.
During late 20th and early 21st century, Tanzania's trade expanded swiftly while its debt declined. Growing numbers of people began using automobiles, the Internet, and cellular telephones. Tanzania's cities grew fast, but the rapid population growth created more unemployment. Although some people became rich, poverty became more widespread. Tanzania's large refugee population––over 500,000 refugees from Burundi and Congo (Kinshasa)––also strained its economy.