The town was named after the Native American word for the Kaskaskia River. The site of Kaskaskia had been a Native American village for thousands of years. In 1703 French Jesuit missionaries started a mission. They wanted to change the Illini (Native American) people's religion to Catholicism. The first stone church was built in 1714. The French also had a fur trading post at the village. French settlers came to farm and mine lead on the Missouri side of the river. In 1718 Kaskaskia became the capital of Upper Louisiana and a fort, Fort de Chartres,was built.