The Cree band joined Treaty #6 on September 9, 1876 at Fort Pitt, Saskatchewan. At the time of signing, the band did not have a chief and band councilor, Makaoo, was appointed to sign. Makaoo and his people settled near a lake that came to be known as Onion Lake. Many Legends exist in relation to the naming of the lake. One story relates the name to wild onions growing in abundance around the lake. ‘The name came from a lake in the middle of the reserve; the lake in turn got its name from the onions as a sort of spring tonic after a winter of moose, deer, and buffalo meat.’ (What’s In A Name, E.T. Russel, 1981). Following the signing of Treaty #6 in 1876, Seekaskootch became Chief. He participated in the surveying of Seekaskootch Reserve, which established in 1889 northwest of Fort Pitt. Seekaskootch was killed in the 1885 rebellion at Steele Narrows while attempting to make peace. He was unarmed at his death.
Seekashootch and Weemisticooseahwis (Makaoo) bands amalgamated on January 16, 1914 and became the Onion Lake Band. Historically, band members made their living at ranching hunting, trapping, and fishing. Onion Lake is the largest Treaty Land Entitlement Reserve in Saskatchewan and the first reserve created under the Saskatchewan Claims and Implementation Act: Bill C-37.
Today Onion Lake Cree Nation is a continually growing membership with and estimated 4956 (2010 PCD list) band members, 3000 of which are living on reserve.