The ship, originally designated a "patrol gunboat," PG-199, was ordered by the United States Maritime Commission under a U.S. Navy contract as USS Peyton.

She was reclassified as a "patrol frigate," PF-91, on 15 April 1943 and laid down by the Walsh-Kaiser Company at Providence, Rhode Island, on 16 October 1943.

[1] With her modifications complete, Tortola reported to the 20th Escort Group – which also included her sister ships Bahamas, Papua, Pitcairn, and Somaliland and the frigate Tavy – on 3 October 1944.

Her first assignment was as an escort for Convoy KMF 35, consisting of six merchant ships, which departed the River Clyde in Scotland on 20 October 1944 bound for Port Said, Egypt, via the Mediterranean Sea.

German submarines and aircraft attacked the convoy on 11 and 12 December 1944, badly damaging the British destroyer HMS Cassandra.

She quickly got back underway to join the escort of Convoy KMF 39 on 28 January 1945 for a voyage to Gibraltar which ended on 5 February 1945.

[1] With her repairs complete, Tortola departed Gibraltar on 20 February 1945 as part of the escort of Convoy MKF 39 bound for the United Kingdom, but on 21 February 1945 she ran aground near Gibraltar and suffered serious damage, losing her starboard bilge keel and opening her fuel tank to the sea.