The earliest history of Madagascar is unclear. Africans and Indonesians reached the island in about the 5th cent. A.D., the Indonesian immigration continuing until the 15th cent. From the 9th cent., Muslim traders (including some Arabs) from E Africa and the Comoro Islands settled in NW and SE Madagascar. Probably the first European to see Madagascar was Diogo Dias, a Portuguese navigator, in 1500. Between 1600 and 1619, Portuguese Roman Catholic missionaries tried unsuccessfully to convert the Malagasy. From 1642 until the late 18th cent. the French maintained footholds, first at Taolagnaro (formerly Fort-Dauphin) in the southeast and finally on Sainte Marie Island off the east coast.

By the beginning of the 17th cent. there were a number of small Malagasy kingdoms, including those of the Antemoro, Antaisaka, Bétsiléo, and Merina. Later in the century the Sakalawa under Andriandahifotsi conquered W and N Madagascar, but the kingdom disintegrated in the 18th cent. At the end of the 18th cent. the Merina people of the interior were united under King Andrianampoinimerina (reigned 1787–1810), who also subjugated the Bétsiléo. Radama I (reigned 1810–28), in return for agreeing to end the slave trade, received British aid in modernizing and equipping his army, which helped him to conquer the Betsimisáraka kingdom. The Protestant London Missionary Society was welcomed, and it gained many converts, opened schools, and helped to transcribe the Merina language. Merina culture began to spread over Madagascar.

Radama was succeeded by his wife Ranavalona I (reigned 1828–1861), who, suspicious of foreigners, declared (1835) Christianity illegal and halted most foreign trade. During her rule the Merina kingdom was wracked by intermittent civil war. Under Radama II (reigned 1861–63) and his widow and successor Rasoherina (reigned 1863–68) the anti-European policy was reversed and missionaries (including Roman Catholics) and traders were welcomed again. Rainilaiarivony, the prime minister, controlled the government during the reigns of Ranavalona II (1868–83) and Ranavalona III (1883–96); by then the Merina kingdom included all Madagascar except the south and part of the west. Ranavalona II publicly recognized Christianity, and she and her husband were baptized.

In 1883 the French bombarded and occupied Toamsina (then Tamatave), and in 1885 they established a protectorate over Madagascar, which was recognized by Great Britain in 1890. Rainilaiarivony organized resistance to the French, and there was heavy fighting from 1894 to 1896. In 1896, French troops under J. S. Gallieni defeated the Merina and abolished the monarchy.

By 1904 the French fully controlled the island. Under the French, who governed the Malagasy through a divide-and-rule policy, development was concentrated in the Tananarive region, and thus the Merina benefited most from colonial rule. Merina nationalism developed early in the 20th cent., and in 1916 (during World War I) a Merina secret society was suppressed by the French after a plot against the colonialists was discovered.

During World War II, Madagascar was aligned with Vichy France until 1942, when it was conquered by the British; in 1943 the Free French regime assumed control. From 1947 to 1948 there was a major uprising against the French, who crushed the rebellion, killing between 11,000 and 80,000 (estimates vary) Malagasy in the process. As in other French colonies, indigenous political activity increased in 1956, and the Social Democratic party (PSD), led by Philibert Tsiranana (a Tsimihety), gained predominance in Madagascar.

On Oct. 14, 1958, the country—renamed the Malagasy Republic—became autonomous within the French Community and Tsiranana was elected president. On June 26, 1960, it became fully independent. Under Tsiranana (reelected in 1965 and 1972), an autocratic ruler whose PSD controlled parliament, government was centralized, the coastal peoples (côtiers) were favored over those of the interior (especially the Merina), and French economic and cultural influence remained strong. Beginning in 1967, Tsiranana cultivated economic relations with white-ruled South Africa.

In 1972, students and workers, discontented with the president's policies and with the deteriorating economic situation, staged a wave of protest demonstrations. At the height of the crisis Tsiranana handed over power to Gen. Gabriel Ramanantsoa, who became prime minister. In Oct., 1972, a national referendum overwhelmingly approved Ramanantsoa's plan to rule without parliament for five years; Tsiranana, who opposed the plan, resigned the presidency shortly after the vote.

Ramanantsoa freed political prisoners jailed by Tsiranana, began to reduce French influence in the country, broke off relations with South Africa, and generally followed a moderately leftist course. In 1975, a new constitution was approved that renamed the Malagasy Republic the Democratic Republic of Madagascar. That same year, Ramanantsoa dissolved his government in response to mounting unrest in the military and internal disagreements regarding economic policy. Col. Ratsimandrava assumed power but was assassinated a month later and Lt. Comdr. Didier Ratsiraka was elected president in a referendum.

The military-backed Supreme Revolutionary Council (CSR), with Ratsiraka as its head, comprised the government's executive branch. Ratsiraka's Marxist-socialist government nationalized most of the economy and borrowed widely to pay for major investments in development. The nation fell into a crippling debt crisis. Ratsiraka's policies of censorship, regional divisiveness, and repression led to several coup attempts in the 1980s, while food shortages and price increases caused further social unrest. In foreign affairs, Madagascar under Ratsiraka strengthened ties with the United States and Europe and continued to distance itself from South Africa.

Ratsiraka was reelected in 1989 under suspicious circumstances and rioting ensued. Madagascar's political and economic upheaval prompted the government to establish a multiparty system and move toward the privatization of industry in the 1990s. After demonstrations and a lengthy general strike in 1991, Ratsiraka agreed to share power with opposition leader Albert Zafy in a transitional government. In a free presidential election held in 1993, Zafy overwhelmingly defeated Ratsiraka.

In 1995, Zafy won passage of a constitutional amendment allowing the president, rather than the national assembly, to choose a prime minister. With the economy deteriorating, protesters staged street demonstrations in Feb., 1996, and there were some calls for an army takeover. Dissatisfaction with Zafy led to his impeachment by the national assembly in July, 1996. In elections later that year, Ratsiraka came back to defeat Zafy, promising a program of humanistic and ecological development; he also announced plans for a referendum to revise the constitution. Elections in 1998 sent 63 members of Ratsiraka's AREMA party into the newly enlarged national assembly.

In the Dec., 2001, presidential elections, opposition leader Marc Ravalomanana claimed victory over Ratsiraka, but the government announced that he had won only 46% of the vote, forcing a runoff. Ravalomanana denounced reported results and proclaimed himself president, creating a standoff between his and Ratsiraka's supporters. Although Ravalomanana gained control of the capital, Ratsiraka moved his government to Toamasina and had strong support outside the capital and in much of the army.

A recount in Apr., 2002, which was negotiated by the Organization of African Unity (OAU) and agreed to by both candidates, declared Ravalomanana the winner, but Ratsiraka rejected those results. Forces supporting Ravalomanana gradually won control of most of the island (except Toamasina prov.) by early July, when Ratsiraka fled Madagascar. The African Union, the OAU's successor, initially refused to recognize the new government and called for new elections. In Dec., 2002, Ravalomanana's party won a majority in elections for a new legislature, and the African Union subsequently recognized the new government. Ratsiraka was tried in absentia and convicted on charges of embezzlement in 2003.

Ravalomanana has moved to privatize state-owned companies and has successfully sought international aid and foreign investment. His government has, however, sometimes limited freedom of the press and other political freedoms. In 2005 the government banned the New Protestant Church (FPVM), a growing charimatic church that had split (2002) from the mainline Reformed Protestant Church of Jesus Christ (FJKM). The president, a lay leader in the FJKM, was accused of favoring one church over another in violation of the constitution, but the courts refused to overturn the decision.

The president was reelected in Dec., 2006, but the election was marred by the exclusion of a major opposition candidate, Pierrot Rajaonarivelo, who was in exile and was not allowed to return and register for the election. In addition, in November, there was an attempted coup against the president by a retired army general who was also not allowed to run; although it was unsuccessful, many of the presidential candidates called his a coup a move in defense of the constitution. In late 2006 and early 2007 Madagascar suffered its worst cyclone (hurricane) season in memory, with six storms hitting the country, affecting some 450,000 inhabitants. Legislative elections in Sept., 2007, again gave the president's party a majority of the seats.