Type C1 was a designation for small cargo ships built for the U.S. Maritime Commission before and during World War II. The first C1 types were the smallest of the three original Maritime Commission designs, meant for shorter routes where high speed and capacity were less important. Only a handful were delivered prior to Pearl Harbor. But many C1-A and C1-B ships were already in the works and were delivered during 1942. Many were converted to military purposes including troop-transports during the war.