thumb|text-bottom|alt=Rear Admiral Murray presenting awards to crew members of HMCS St. Croix, which sank the German submarine U-90 on 24 July 1942| Rear Admiral Murray presenting awards to crew members of , which sank the German submarine on 24 July 1942On his return to Canada, and at the request of British Admiral Sir Dudley Pound,Lund (2001), p. 299 on 13 June 1941 Murray was put in charge of the Newfoundland Escort Force based out of St John's. This was the most important operational mandate given to a Royal Canadian Navy officer until that point,German, p. 92 in full command of 6 Canadian destroyers, 7 British destroyers, and 21 corvettes, and with responsibility for convoy escort from New York out as far as the transfer point to UK escorts south of Iceland.
