Silas Dennison McLellan, CM (17 March 1897 – 10 February 1974) was a Canadian marathon runner. He won the five times as well as competing in the Boston marathon, the 1928 Summer Olympics and the British Empire Games. Military Service Silas was drafted on the 11th of June 1918 at Camp Aldershot. He joined the 1st Depot Battalion Nova Scotia Regiment. He arrived in Liverpool on the 16th of August 1918 with the 17th reserve battalion. He remained in the United Kingdom until June of 1919 when he returned to Canada and was discharged on the 5th of July 1919 in Halifax, Nova Scotia.