to the U.S. origin), St. Croix was named after the St. Croix River forming the border between Maine and New Brunswick. Royal Canadian Navy service The destroyer sailed for the United Kingdom on 30 November via St. John's, Newfoundland but encountered a hurricane en route and was forced to return to Canada. HMCS St. Croix arrived at Halifax on 18 December and underwent repairs which kept the destroyer inactive until March 1941. On 14 March 1941 St. Croix assumed local escort and patrol duties in Canadian waters. At the end of August she joined the Newfoundland Escort Force and plied between St. John's and Reykjavík, Iceland. St. Croix underwent a six-month refit at Saint John, New Brunswick, returning to service in May 1942. By May 1942 the Newfoundland Escort Force had been renamed the Mid-Ocean Escort Force and its range extended to Londonderry Port. St. Croix sank the on 24 July 1942, which, with other U-boats, had attacked her convoy (ON 113) on 23 July, sinking two merchant vessels and damaging a third. On the return voyage, Convoy ON 127 was attacked by 13 U-boats. Between 10 September and 14 September eleven merchant ships and one destroyer were lost. En route from Londonderry Port to Gibraltar on 4 March 1943 with convoy KMS 10, she assisted the corvette in the sinking of some off the Iberian coast. With the addition of air escort to convoy defense in 1943, U-boat tolls in the North Atlantic diminished and many of the boats were withdrawn during the summer. In the fall, however, Germany began a new U-boat offensive. On 16 September, St. Croix, then on her first patrol with an offensive striking group in the Bay of Biscay, went to the aid of convoy ONS 18, followed by ON 202, both heavily beset by a wolfpack. The defense of these convoys resulted in a long-running battle with losses to both sides. The convoys lost three escorts and six merchantmen, with two escorts damaged. The wolfpack lost three U-boats. St. Croix was the first escort to be sunk, taking three hits from U-305 in the stern on 20 September. was sunk by as she came up to screen HMS Itchen's rescue operations. Itchen, forced to retire that evening, returned the next morning and picked up 81 survivors from St. Croix and one from Polyanthus. The following day, 22 September, Itchen herself was torpedoed. Three