Marquesas Islands (French Îles Marquises), island group, French Polynesia (an overseas territory of France), in the southern Pacific Ocean. The ten volcanic islands of the group are mountainous and fertile; breadfruit, coconut, and tobacco are grown here. Hiva Oa, the largest island of the group, is the site of the grave of the French painter Paul Gauguin. Nuku Hiva, the second largest, contains the administrative seat, Hakapehi. The islands were annexed by France in 1842. Total area, 1,274 sq km (492 sq mi); population (1988) 7,538.