Kingsley and other landowners along the St. Johns became involved in the Patriot War, an attempt by expansionists in the United States to take over Florida from the Spanish. In July of 1812, Kingsley hosted a legislative council at Laurel Grove that established the goal of acquiring the East Florida Territory and giving it to the United States. During the Seminole Indian Wars (1836-1841), the river was used to transport troops and supplies for the United States government. Several forts were built along the St. Johns River, including Fort Shannon in Palatka, Fort Kingsbury and Fort Mellon, which were built along Lake Monroe, and Fort Heilman that was built at the forks of Black Creek in 1836.