Into 1943 she screened the convoys assembled at Espiritu Santo and Nouméa to "Cactus" area (Guadalcanal and Tulagi), guarded them as they off-loaded and then returned the vessels to their departure point.

Periodically assigned to offensive duties she also conducted antisubmarine hunter-killer missions off Allied harbors, sweeps of "the Slot", bombarded shore targets and performed gunfire support missions for Marine and Army units as they pushed toward the Tenamba River and total control of the long embattled island.

En route back to Tulagi Nicholas, in company with De Haven (DD-469) and 3 LCTs, was attacked by a formation of 14 Aichi D3A "Val" dive bombers.

As her sister destroyer settled in the waters of Ironbottom Sound, Nicholas fought off eight planes, receiving only near misses which killed two of her crew and damaged the steering gear.

[2] Nicholas and Radford (DD-446) were later awarded Presidential Unit Citations[3] for their persevering performance during the Battle of Kula Gulf—a token, Admiral Chester Nimitz told the crew, of "the respect and esteem which this ship, her officers and men have well earned throughout the Navy."

In early August, she joined Task Unit 31.5.1 (TU31.5.1) and on the 15th screened the advance transport group during landings at Barakoma, Vella LaVella.

Back at Tulagi on the 17th, she, with O'Bannon (DD-450), Taylor (DD-468), and Chevalier (DD-451), was sent out to intercept four Rabaul-based Japanese destroyers (Sazanami, Hamakaze, Isokaze, Shigure) commanded by Rear-Admiral Baron Matsuji Ijuin providing heavy cover for an amphibious convoy tasked with the establishment of a barge staging area at Horaniu on Vella LaVella in order to facilitate the evacuation of 9,000 troops from the island.

The American force pursued, scored on Isokaze, and finally dropped behind, engineering problems in Chevalier limiting them to 30 knots (56 km/h).

On 11 November Nicholas departed Nadi, Fiji Islands, with Task Group 50.1 (TG50.1) for raids on Kwajalein and Wotje, after which she headed east, arriving at San Francisco 15 December for overhaul.

On 6 December she assisted in a sweep of the Camotes Sea, bombarded Japanese Naval facilities on Ormoc Bay and then covered Allied landings there.

En route to Luzon, her group was harassed by enemy midget submarines and almost constant air raids.

On the 24th, she captured a motor boat being used by three Japanese to escape from the island and on the 29th provided close cover for the landings in Zambales Province.

Resuming escort work on the 17th, she guarded minesweepers as they cleared Basilan Strait in mid-March and then supported the occupation of the Zamboanga area.

she returned to Luzon to support the Sixth Army as it fought to reoccupy the island and then on the 24th resumed operations in the Netherlands East Indies.

Following strikes on Sakishima, she joined TG30.8 at Ulithi and screened that group as it refueled and resupplied the fast aircraft carriers at sea.

Decommissioned 12 June 1946, Nicholas remained in the Pacific Reserve Fleet until hostilities in Korea necessitated her recall.

Recommissioned 19 February 1951, she underwent shakedown off the west coast, steamed to Pearl Harbor where she joined CortDesDiv 12, CortDesRon 1; and continued on to the Western Pacific, arriving at Yokosuka 10 June.

In Far Eastern waters until 14 November, she screened the carriers of TF77 off the west coast of Korea; conducted ASW exercises between Yokosuka and Okinawa; and patrolled the Taiwan Strait.

A temporary replacement vessel in DesDiv 112, she served first with TF77 and then swung around the peninsula to the gun line off the Korean east coast and operated there, under CTF95, until sailing for home in July.

Her 7th Fleet deployments took her from Japan to Sumatra, while EastPac assignments ranged primarily from Hawaii to the west coast.

Relieved of duty 15 April, Nicholas returned to Pearl Harbor only to depart again for Viet Nam in mid-September.

Early in 1966 she returned to Viet Nam for duty on "Yankee Station" in the Gulf of Tonkin, followed by another tour on "Market Time" patrol.

Forced to clear the area on three occasions during rescue operations, she gallantly fought off continuing attacks by Japanese warships emerging from Kula Gulf and, with the other destroyer, sank or damaged an enemy light cruiser and two destroyers with deadly torpedo and gunfire, returning to the area after each onslaught to complete the heroic rescue of more than seven hundred survivors.