High Quality Content by WIKIPEDIA articles! The Captain class was a designation given to 78 frigates of the Royal Navy, constructed in the United States of America, launched in 1942–1943 and delivered to the United Kingdom under the provisions of the Lend-Lease agreement (under which the United States of America supplied the United Kingdom and other Allied nations with materiel between 1941 and 1945), they were drawn from two sub-classes of the American destroyer escort (originally British destroyer escort) classification: 32 from the Evarts sub-class and 46 from the Buckley sub-class. Upon reaching the UK the ships were substantially modified by the Royal Navy, making them distinct from the US Navy destroyer escort ships.