The largest coastal groups are the Betsimisaraka (1.5 million) and the Tsimihety and Sakalava (700,000 each).

The Malagasy language is of Malayo-Polynesian origin and is generally spoken throughout the island. French is spoken among the educated population of this former French colony. English is becoming more widely spoken, and in 2003 the government began a pilot project of introducing the teaching of English into the primary grades of 44 schools, with hopes of taking the project nationwide.

Most people practice traditional religions, which tend to emphasize links between the living and the dead. They believe that the dead join their ancestors in the ranks of divinity and that ancestors are intensely concerned with the fate of their living descendants. The Merina and Betsileo reburial practice of famadihana, or "turning over the dead" celebrate this spiritual communion. In this ritual, relatives' remains are removed from the family tomb, rewrapped in new silk shrouds, and returned to the tomb following festive ceremonies in their honor.

About 45% of the Malagasy are Christian, divided almost evenly between Roman Catholic and Protestant. Many incorporate the cult of the dead with their religious beliefs and bless their dead at church before proceeding with the traditional burial rites. They also may invite a pastor to attend a famadihana. While many Christians continue these practices, others consider them to be superstitions that should be abandoned. Many of the Christian churches are influential in politics. In the coastal regions of the provinces of Mahajanga and Antsiranana (Diego Suarez), Muslims constitute a significant minority. Muslims are divided between those of Malagasy ethnicity, Indo-Pakistanis, and Comorians.

The written history of Madagascar began in the seventh century A.D., when Arabs established trading posts along the northwest coast. European contact began in the 1500s, when Portuguese sea captain Diego Dias sighted the island after his ship became separated from a fleet bound for India. In the late 17th century, the French established trading posts along the east coast. From about 1774 to 1824, it was a favorite haunt for pirates, including Americans, one of whom brought Malagasy rice to South Carolina.

Beginning in the 1790s, Merina rulers succeeded in establishing hegemony over the major part of the island, including the coast. In 1817, the Merina ruler and the British governor of Mauritius concluded a treaty abolishing the slave trade, which had been important in Madagascar's economy. In return, the island received British military and financial assistance. British influence remained strong for several decades, during which the Merina court was converted to Presbyterianism, Congregationalism, and Anglicanism.

The British accepted the imposition of a French protectorate over Madagascar in 1885 in return for eventual control over Zanzibar (now part of Tanzania) and as part of an overall definition of spheres of influence in the area. Absolute French control over Madagascar was established by military force in 1895-96, and the Merina monarchy was abolished.

Malagasy troops fought in France, Morocco, and Syria during World War I. After France fell to the Germans, the Vichy government administered Madagascar. British troops occupied the strategic island in 1942 to preclude its seizure by the Japanese. The Free French received the island from the United Kingdom in 1943.

In 1947, with French prestige at low ebb, a nationalist uprising was suppressed after several months of bitter fighting. The French subsequently established reformed institutions in 1956 under the Loi Cadre (Overseas Reform Act), and Madagascar moved peacefully toward independence. The Malagasy Republic was proclaimed on October 14, 1958, as an autonomous state within the French Community. A period of provisional government ended with the adoption of a constitution in 1959 and full independence on June 26, 1960.