In 1715, a revolt of "poor white" smallholders in the north of Martinique, known as La Gaoulé, caused settlers to migrate to southern Dominique, where they set up smallholdings. Meanwhile, French families and others from Guadeloupe settled in the north. In 1727, the first French commander, M. Le Grand, took charge of the island with a basic French government. Dominique formally became a colony of France, and the island was divided into districts or "quarters". The French had already developed plantation agriculture on Martinique and Guadeloupe, where they cultivated sugarcane with enslaved African workers. In Dominique they gradually developed coffee plantations. They forcefully trafficked so many African slaves to fill the labour demands that the population became predominantly African in ethnicity.