Following shakedown, DesDiv 15 moved to Pearl Harbor. Operating with the Pacific Fleet beginning in April 1940, it spent a nearly a year participating in fleet problems, training exercises and escort duties. In June 1941, it returned to the Caribbean and Atlantic for carrier and antisubmarine training, and to join DesDiv 16 in neutrality patrols.

In early 1942, Wasp (CV 7), with Wainwright, Lang, Mayrant, Rowan, Sterett and Wilson, was temporarily attached to the British Home Fleet at Scapa Flow. During this period, while the destroyers drew such assignments as patrolling the Denmark Strait, hoping the battleship Tirpitz would not appear as its sister Bismarck had done the previous year, Lang escorted Wasp in two missions into the Axis-dominated Mediterranean Sea to fly off fighter planes for the defense of Malta; Sterett was also in the formation on the second trip.

In June, Division 15 was withdrawn from this duty to Norfolk with Wasp, which it and Farenholt, with battleship North Carolina and cruisers Quincy and San Juan, escorted onward to the South Pacific. There, the division accumulated a long and distinguished record and, initially joined by Ellet, was renumbered as DesDiv 4 of DesRon 2 in 1944.

Flagship Wainwright and Division 16, meanwhile, remained in the Atlantic, operating interchangeably with the newer Benson- and Gleaves-class destroyers on convoy duty.

• On 1 July, Rowan sortied from Seyðisfjörður on Iceland’s east coast with a cruiser force to cover Convoy PQ-17 from Hvalfjörður to Arkhangelsk, Russia. On the 2nd, she joined the convoy’s screen and shot down one attacking aircraft, but attacks continued for a week until the convoy was ordered to scatter. Only 11 of its 35 merchant ships got through.
• In November 1942, DesDiv 16 operated in Operation “Torch,” the invasion of North Africa. Wainwright, Mayrant and Rhind and Jenkins were attached to a covering group with battleship Massachusetts and heavy cruisers Tuscaloosa and Wichita that engaged targets at Casablanca.
• In March 1943, the division plus Champlin and Hobby formed the escort for 45 merchantmen in convoy UGS-6, which faced a U-boat wolfpack. Although as many as ten U-boats converged on the convoy, the radar-equipped destroyers fought them off. Only three ships were lost.

On 23 May, the division moved into the Mediterranean, where it began escorting convoys between Mers-el-Kébir, Algeria and Bizerte, Tunisia and conducting anti-submarine patrols. In June, all five ships were with supply echelons for Operation “Husky,” the landings on Sicily’s south coast.

DesRon 8 in North Africa and the Mediterranean.

Moving around to the island’s north coast, Mayrant was damaged off Palermo on 26 July by a near miss from a German bomber. She remained at Palermo under threat of air attack until 9 August, when she was towed to Malta for repairs that lasted until 14 November. Under her own power again, she steamed to the Charleston Navy Yard for more extensive work, returning to Atlantic convoy duty only the following May.

Less Mayrant, the division continued to the Italian mainland for Operation “Avalanche” at Salerno in September 1943. It was the last invasion for two ships:

• On 11 September, Rowan was torpedoed and lost, along with three quarters of her crew, while escorting a convoy back to Oran.
• Rhind suffered near misses from German bombers in both July and September. After repairs, she spent the remainder of the war until May 1945 in Atlantic convoy and patrol duty.

Of the original DesRon 8, this left Trippe and Wainwright alone in the Mediterranean.

• On 13 October, both ships rescued survivors after U-571 torpedoed and sank Bristol, which was escorting a convoy from Naples to Oran.
• On 13 December north of Algiers, Wainwright, Niblack, Benson and HMS Calpe made contact with U-593. Depth charge attacks forced her to surface where Wainwright worked her over with gunfire and then rescued survivors as she sank.

In January 1944, both destroyers joined Operation “Shingle” following the landings at Anzio, for which they provided fire support until 10 February. Thereafter, for more than a year, like Mayrant and Rhind, they returned to a normal range of Atlantic theater assignments.

In the spring of 1945, all four ships went to the Pacific—Wainwright in April and Mayrant, Trippe and Rhind in May.