Founded by French settlers in the 17th century, Saint-Louis became urbanized in the mid-19th century. She was the capital of Senegal from 1872 to 1957 and played a major cultural and economic role in the whole of West Africa. The situation of the city on an island at the mouth of the river Senegal, its regular urban plan, its system of quays and its characteristic colonial architecture give Saint-Louis its special quality and identity.