The United States Maritime Commission (MARCOM) was an agency of the United States government that was created by the Merchant Marine Act of 1936, passed by Congress on 29 June 1936 and replaced the U.S. Shipping Board which had existed since World War I. It was intended to formulate a merchant shipbuilding program to design and build five hundred modern merchant cargo ships to supplement and replace the World War I vintage vessels, including Hog Islander ships, that comprised the bulk of the U.S. Merchant Marine.