The River-class frigate was a class of 151 frigates launched between 1941 and 1944 for use as anti-submarine convoy escorts in the North Atlantic. The majority served with the Royal Navy (RN) and Royal Canadian Navy (RCN), with some serving in the other Allied navies; the Royal Australian Navy (RAN), the Free French Navy (FFN), the Royal Netherlands Navy and, post-war, the South African Navy (SAN). Ten ships built in Canada were assigned to the United States Navy (USN) to cover for a shortage of suitable convoy escorts until American-built ships became available. In the event, only two were commissioned in the USN, the remaining eight were commissioned in the RN and RCN. Twelve River-class frigates were built in Australia for the RAN (four to a modified design), the last of which is HMAS D