Based on evidence from a French-Wolof phrase book published in Senegal in 1864, this article makes the case that urban Wolof, a variety of the language characterized by significant lexical borrowing from French, is a much older variety than scholars have generally claimed. Historical evidence suggests that urban Wolof emerged in the 18th and 19th centuries in the coastal island city of Saint-Louis du Sénégal, France's earliest African settlement and future capital of the colonial entity that would be known as French West Africa. The intimate nature of early contact between African and European populations and the later role played by the métis or mixed-race population of the island as linguistic brokers contributed to a unique, urban variety of Wolof that has important links to today's variety of urban Wolof spoken in Dakar and other cities throughout the country.