Tanzania assumed its present form in 1964 after a merger between the mainland Tanganyika and the island of Zanzibar, which had become independent the previous year.
Unlike many African countries, whose potential wealth contrasted with their actual poverty, Tanzania had few exportable minerals and a primitive agricultural system.
In an attempt to remedy this, its first president, Julius Nyerere, issued the 1967 Arusha Declaration, which called for self-reliance through the creation of cooperative farm villages and the nationalisation of factories, plantations, banks and private companies.
Politics: Tanzania has enjoyed stability. Multi-party politics was introduced in 1992
Economy: Annual growth rate has averaged 6.7% since 2006, one of the best in sub-Sahara Africa. Power supplies are erratic and fall short of demand. Gold earnings have been rising, and the find of a major offshore gas field is promising
International: Tanzania hosts thousands of refugees from conflict in the neighbouring Great Lakes region
Environment: Experts fear a planned highway threatens the Serengeti game park, Tanzania's biggest draw for tourism. Poaching is a major issue
Country profiles compiled by BBC Monitoring
But a decade later, despite financial and technical aid from the World Bank and sympathetic countries, this programme had completely failed due to inefficiency, corruption, resistance from peasants and the rise in the price of imported petroleum.
Tanzania's economic woes were compounded in 1979 and 1981 by a costly military intervention to overthrow President Idi Amin of Uganda.
After Mr Nyerere's resignation in 1985, his successor, Ali Hassan Mwinyi, attempted to raise productivity and attract foreign investment and loans by dismantling government control of the economy.
This policy continued under Benjamin Mkapa, who was elected president in 1995. The economy grew, though at the price of painful fiscal reforms.
Tourism is an important revenue earner; Tanzania's attractions include Africa's highest mountain, Kilimanjaro, and wildlife-rich national parks such as the Serengeti.
Tanzania has become a target for poachers, and conservationists have warned that the current rate at which elephants are being killed for their ivory the entire population could die out by the end of the decade.
The political union between Zanzibar and mainland Tanzania has weathered more than four decades of change. Zanzibar has its own parliament and president.