In order to support this effort and to cut off Japanese reinforcements from moving down the Munda trail from Bairoko, the Allies decided to land a force on the north shore of New Georgia on 5 July.

[4][5] The night before the battle in the Kula Gulf, Rear Admiral Walden L. Ainsworth's Task Group 36.1 (TG 36.1) conducted a cruiser bombardment of Vila on Kolombangara Island and Bairoko.

This operation was undertaken to support a landing at Rice Anchorage on the northern shore of New Georgia, by U.S. Marine and U.S. Army troops tasked with capturing Enogai and Bairoko.

[6] At the same time as the Marines were landing at Rice Anchorage, two U.S. Navy destroyers, USS Strong and Chevalier, entered Bairoko Harbor to provide naval gunfire support.

In the early hours of the morning a Type 93 torpedo hit Strong on her port side aft, resulting in the loss of the destroyer.

On the afternoon of 5 July, they were returning to the Coral Sea to resupply when Admiral William Halsey was informed of another "Tokyo Express" mission down "the Slot" in the Solomon Islands, from Buin, on Bougainville.

About an hour later, Ainsworth's task force was off the east coast of Kolombangara, about half a mile from Visu Visu Point, and roughly northeast of Waugh Rock,[13] when they came into contact with a Japanese naval reinforcement group consisting of two transport units carrying troops, escorted by a support unit, under Admiral Teruo Akiyama.

[21] Mikazuki and Hamakaze completed unloading, and departed through the Blackett Strait, while Mochizuki lingered for another hour before leaving through the Kula Gulf along the coast of Kolombangara, clashing briefly with Nicholas, around 06:15 before withdrawing behind a smoke screen.

[21] For his actions leading the column of cruisers at Kula Gulf and earlier in the campaign, Captain Robert W. Hayler of the Honolulu received his second Navy Cross.

Amagiri escaped and later rammed and cut in half the motor torpedo boat PT-109, captained by future President of the United States John F. Kennedy (1917–1963), in the Blackett Strait, southwest of Kolombangara on 2 August.