After the Spanish Empire conquered Cuba, its Arawak and Ciboney populations dramatically declined. The Spanish then turned to slaves sold at West African ports as a labor source for Cuba's sugar, tobacco, and coffee plantations. Slavery was widespread in West Africa, where prisoners of war and certain criminals were enslaved. Between 702,000 and 1 million enslaved Africans were brought to Cuba, the earliest in 1511, although the majority in the 19th century. In Cuba, slaves were divided into groups termed "naciones" (nations), often based on their port of embarkation rather than their own ethno-cultural background.