Johannes Waldemar "Walter" Koski was born in 1909 in Winona, Michigan. His father was a miner and his mother ran a boarding house at the King Philip Mine location. In 1920 the mine was closed due to the falling price of copper and the family returned to Finland. Walter returned to the United States eight years later, via the Quebec lumber camps and Montreal street labor. He worked as a teamster on the Jonas Ruuttila dairy farm in Green, Michigan before he began a long career with cooperatives. He became a clerk in the Ontonagon Co-op Society in 1933. He was later an accountant with the Cooperative Publishing Association, followed by the Controller at the Central Cooperative Wholesale and General Manager of the reorganized Central Cooperatives, Inc. He retired as Treasurer of the Midland Co-op in 1974. Mr. Koski passed away in 2004.