Type C1 was a designation for cargo ships built for the United States Maritime Commission before and during World War II. Total production was 493 ships built from 1940 to 1945. 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.
The Type C1-M ship was a separate design, for a significantly smaller and shallower draft vessel. This design evolved as an answer to the projected needs for military transport and supply of the Pacific Ocean theater of World War II.[1]
Type C1 ships under the control of the British Ministry of War Transport took an Empire name even if built with another name e.g. Cape Turner.