Madagascar (; Malagasy: Madagasikara), officially the Republic of Madagascar (Malagasy: Repoblikan'i Madagasikara [republiˈkʲan madaɡasˈkʲarə̥]; French: République de Madagascar), and previously known as the Malagasy Republic , is an island country in the Indian Ocean , off the coast of East Africa . The nation comprises the island of Madagascar (the fourth-largest island in the world ), and numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian peninsula around 88 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of its wildlife is found nowhere else on Earth . The island 's diverse ecosystems and unique wildlife are threatened by the encroachment of the rapidly growing human population and other environmental threats.
The first archaeological evidence for human foraging on Madagascar dates to 2000 BC. Human settlement of Madagascar occurred between 350 BC and AD 550 by Austronesian peoples, arriving on outrigger canoes from Borneo. These were joined around AD 1000 by Bantu migrants crossing the Mozambique Channel from East Africa . Other groups continued to settle on Madagascar over time , each one making lasting contributions to Malagasy cultural life . The Malagasy ethnic group is often divided into 18 or more subgroups of which the largest are the Merina of the central highlands.
Until the late 18th century, the island of Madagascar was ruled by a fragmented assortment of shifting sociopolitical alliances.