Treaties between the U.S. Government and the Dakota and Ojibwe gradually forced the natives off their lands and onto reservations. In 1861 residents of Mankato formed the Knights of the Forest, with a goal of eliminating all Native Americans from Minnesota. As conditions deteriorated for the Dakota, tensions rose, leading to the Dakota War of 1862. The six-week war ended with the execution of 38 Dakota and the exile of many to the Crow Creek Reservation in Dakota Territory. As many as 800 settlers died during the war. Minnesota Governor Alexander Ramsey subsequently declared that "the Sioux Indians of Minnesota must be exterminated or driven forever beyond the borders of the state.” William Crooks, commander of 6th Minnesota, had a palisade erected around the encampment on Pike island, just below the fort, to protect native people from the soldiers and settlers. Conditions there were poor. The food was meager, measles and cholera swept the enclosure and nothing had been done to provide sanitation. Many died. The men were imprisoned or had fled. Upon becoming Indian Commissioner, Ramsey set out to get the Ojibwe too. In 1863 he negotiated the Treaty of Old Crossing, whereby the Ojibwe ceded all their land in northern Minnesota and moved to reservations.