Crazy Bear (1785-1856) was an Indian chief of the Assiniboine tribes (stone Sioux), a Native American people originally from the Northern Great Plains, their territory comprising Montana, North Dakota, Alberta and Saskatchewan. He is known as a skilled negotiator with the American Fur Company at Fort Union, North Dakota, and for his participation at the Fort Laramie Treaty Council of 1851. He earned the name Mah-To-Wit-Ko (meaning "Crazy Bear") because he fought like a crazy bear.