Boomers is the name given to settlers in the Southern United States who attempted to enter the Unassigned Lands in what is now the state of Oklahoma in 1879, prior to President Grover Cleveland opening them to settlement by signing the Indian Appropriations Act of 1889 on March 2, 1889. Boomers preceded by a decade the Sooners, settlers who entered the Unassigned Lands just prior to the April 22, 1889 official opening. The term "Boomer" relating to Oklahoma refers to participants in the "Boomer Movement," white settlers who believed the Unassigned Lands were public property and open to anyone for settlement, not just Indian tribes. Their belief was based on a clause in the Homestead Act of 1862 which said that any settler could claim of "public land." Some Boomers entered the Unassigned Lands and were removed more than once by the United States Army. Charles C. Carpenter was the earliest leader of the Boomer movement, succeeded by David L. Payne, who was succeeded by William L. Couch. After its founding in 1890, the University of Oklahoma adopted "Boomers" as the nickname of their football team, after having first tried "Rough Riders." In 1908, the name was changed to "Sooners", the current team name.