Tanzania has been spared the internal strife that has blighted many African states.
Though it remains one of the poorest countries in the world, with many of its people living below the World Bank poverty line, it has had some success in wooing donors and investors.
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. 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.
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.
The political union between Zanzibar and mainland Tanzania has weathered more than four decades of change. Zanzibar has its own parliament and president.
President: Jakaya Kikwete
Jakaya Kikwete has been president since his election in 2005 and is now serving his second term, having won re-election in October 2010.
He has been one of the West's darlings in recent years, sometimes touted as a model African leader, and his country a favoured destination for international aid.
However, his political legitimacy has been seen by some to have been somewhat dented in the 2010 elections, when he won 61 percent of the vote, down from 80 percent in 2005, and with a total turnout at only 42%, down from 72% in 2005.
The main opposition Chadema party, whose candidate finished closest to Kikwete, rejected the outcome, alleging fraud.
As a foreign minister between 1995 and 2005, Kikwete was already known in the corridors of international power when he became president.
His tenure as chairman of the African Union was seen as well handled and he is credited with playing a significant role in efforts to find a solution to the post-election chaos that erupted in neighbouring Kenya in 2007.
Kikwete is a veteran of the ruling Chama Cha Mapinduzi (CCM), which has controlled Tanzania since the country's inception and also governs in semi-autonomous Zanzibar.
He perpetuated his predecessor's work to turn Tanzania into a free-market economy while showing respect for the socialist policies of founding father Julius Nyerere.
Mr Kikwete, a former military officer, was born in October 1950 and is married with eight children.
His predecessor Benjamin Mkapa retired after 10 years in power. He was credited with being the driving force behind Tanzania's extensive economic liberalisation, which was well received by the IMF and World Bank.
Under his presidency inflation dropped, the economy grew and Tanzania's foreign debt was wiped. But Mr Mkapa's critics said that, behind the statistics, most Tanzanians remained impoverished.
A chronology of key events:
1498 - Portuguese explorer Vasco da Gama visits Tanzanian coast.
1506 - Portuguese succeed in controlling most of the East African coast.
1699 - Portuguese ousted from Zanzibar by Omani Arabs.
1884 - German Colonisation Society begins to acquire territory on the mainland.
1886 - Britain and Germany sign an agreement allowing Germany to set up a sphere of influence over mainland Tanzania, except for a narrow piece of territory along the coast which stays under the authority of the sultan of Zanzibar, while Britain enjoys a protectorate over Zanzibar.
1905-06 - Indigenous Maji Maji revolt suppressed by German troops.
British rule
1916 - British, Belgian and South African troops occupy most of German East Africa.
1919 - League of Nations gives Britain a mandate over Tanganyika - today's mainland Tanzania.
1929 - Tanganyika African Association founded.
1946 - United Nations converts British mandate over Tanganyika into a trusteeship.
1954 - Julius Nyerere and Oscar Kambona transform the Tanganyika African Association into the Tanganyika African National Union.
Independence
1961 - Tanganyika becomes independent with Julius Nyerere as prime minister.
1962 - Tanganyika becomes a republic with Nyerere as president.
1963 - Zanzibar becomes independent.
1964 - Sultanate of Zanzibar overthrown by Afro-Shirazi Party in a violent, left-wing revolution; Tanganyika and Zanzibar merge to become Tanzania, with Nyerere as president and the head of the Zanzibar government and leader of the Afro-Shirazi Party, Abeid Amani Karume, as vice-president.
1967 - Nyerere issues the Arusha Declaration, which calls for egalitarianism, socialism and self-reliance.
1977 - The Tanganyika African National Union and Zanzibar's Afro-Shirazi Party merge to become the Party of the Revolution, which is proclaimed as the only legal party.
1978 - Ugandans temporarily occupy a piece of Tanzanian territory.
1979 - Tanzanian forces invade Uganda, occupying the capital, Kampala, and help to oust President Idi Amin.
Multi-party politics
1985 - Nyerere retires and is replaced by the president of Zanzibar, Ali Mwinyi.
1992 - Constitution amended to allow multi-party politics.
1995 - Benjamin Mkapa chosen as president in Tanzania's first multi-party election.
1999 October - Julius Nyerere dies.
2000 - Mkapa elected for a second term, winning 72% of the vote.
2001 26 January - Tanzanian police shoot dead two people in Zanzibar while raiding the offices in Zanzibar town of the Civic United Front (CUF) party.
CUF chairman Ibrahim Lipumba charged with unlawful assembly and disturbing the peace.
Zanzibar violence
2001 27-28 January - At least 31 people are killed and another 100 arrested in Zanzibar in protests against the government's banning of opposition rallies calling for fresh elections; Tanzanian government sends in troop reinforcements.
2001 March - Governing Chama Cha Mapinduzi (CCM), and main opposition in Zanzibar, CUF, agree to form joint committee to restore calm and to encourage return of refugees from Kenya.
2001 April - Tens of thousands of opposition supporters march through the commercial capital, Dar-es-Salaam, in the first major joint demonstration by opposition parties in decades.
2001 July - Huge new gold mine, Bulyanhulu, opens near northern town of Mwanza, making Tanzania Africa's third largest producer of gold.
2001 November - Presidents of Tanzania, Uganda and Kenya launch regional parliament and court of justice in Arusha to legislate on matters of common interest such as trade and immigration.
2001 December - Britain approves controversial deal to sell military air traffic control system to Tanzania. Critics say it is a waste of money.
2002 June - Nearly 300 killed in Tanzania's worst train disaster after passenger train loses power and rolls into freight train at high speed.
2002 August - Opposition criticises president for ordering presidential jet costing $21m (£14m).
2005 March-April - Political violence in semi-autonomous Zanzibar ahead of voter registration for October poll.
2005 October - Governing CCM wins Zanzibar elections. Opposition CUF claims vote-rigging and announces an indefinite boycott of Zanzibar's parliament.
Kikwete elected
2005 December - Jakaya Kikwete, foreign minister and ruling CCM candidate, wins presidential elections. He replaces Benjamin Mkapa, who retires after a decade at the helm.
2006 April - High Court outlaws traditional practice of entertaining candidates during elections. Critics of "Takrima" - the giving of tips - said it encouraged corruption.
2006 June - Visiting Chinese Prime Minister Wen Jiabao, on his seven-nation African tour to secure energy deals and strengthen economic ties, signs agreements to help Tanzania's health, transport and communications sectors.
2006 August - The African Development Bank announces the cancellation of more than $640m of debt owed by Tanzania, saying it was impressed with Tanzania's economic record and the level of accountability of public finance.
2007 January - Britain's Serious Fraud Office visits Tanzania to probe the controversial purchase of an air traffic control system in 2001. A British paper reports that the British defence company, BAE Systems, allegedly paid a Tanzanian middleman a commission of $12m to win the order.
2007 July - Former US president Bill Clinton launches a programme aimed at making subsidised malaria drugs available in a pilot scheme that could spread to the rest of Africa.
2008 January - Central Bank Governor Daudi Ballali is sacked after an international audit finds the bank made improper payments of more than $120m (£60m) to local companies.
Scandal
2008 February - President dissolves his cabinet following a corruption scandal which forced the premier and two ministers to resign.
2009 November - Opposition party in Zanzibar, the CUF, ends boycott of the island's parliament ahead of upcoming elections.
2010 July - Tanzania joins its neighbours in forming a new East African Common Market, intended to integrate the region's economy.
2010 September - President Kikwete says construction of highway through Serengeti game reserve will go ahead, despite criticism from environmental experts.
2010 October - Kikwete wins re-election.
2010 December - Britain's largest arms manufacturer, BAE Systems, is fined over a controversial contract to supply Tanzania with a radar system.
2011 January - Two killed as police try disperse demonstrators demanding release of opposition leader, detained ahead of a rally against government corruption.
