Established on August 8, 1946, the Merchant Marine World War II Victory Medal honors United States Marine mariners who carried out service onboard merchant ships running American colors between the dates of December 7, 1941 and September 3, 1945 for a minimum term of 30 days. The Merchant Marine consists of civilian mariners who operate privately and federally owned vessels; in wartime, these vessels may be called to provide transportation or other support for military troops or supplies.