 A ship named "Mormacpenn" launched the previous year had been acquired by the Navy to become the .The later "Mormacpenn", sponsored at launch by the wife of the General Counsel of the Maritime Commission, Mrs. Carl F. Farbach, was intended for service on the South American routes of the American Republics Line.The ship was acquired by the United States Navy on 2 June 1941 before any commercial service at Charleston, South Carolina; and commissioned as USS "Markab" (AK 31) on 15 June 1941 with Commander Allen D. Brown in command.