Leander was a light cruiser, the name ship of her class. Devonport Dockyard launched her on 24 September 1931, and the Royal Navy commissioned her on 24 March 1933. By the middle of the Pacific war she was HMNZS Leander, of the Royal New Zealand Navy, flying the White Ensign.
In July 1943 she joined Rear Admiral Walden L. Ainsworth at Tulagi, in the place of Helena, which had been sunk at Kula Gulf on 6 July. On the night of 12–13 July his column was about twenty miles east of the north end of Kolombangara. Honolulu led the cruisers, with Leander and St. Louis astern, five destroyers ahead and five astern.
Rear Admiral Shunji Izaki was coming the other way in Jintsu. His destroyers were Mikazuki, Yukikaze, Hamakaze, Kiyonami, and Yugure. Four more destroyers were carrying troops. The van fired torpedoes. Jintsu was sunk and Izaki was killed. The shot that finished her is not pinned to one ship.
A torpedo hit Leander on the starboard side, about amidships. The National Museum of the Royal New Zealand Navy records twenty-eight men killed and fifteen injured. The ship that fired is not known. She lost power, and she was out of the rest of the night. Temporary repairs got her to Auckland and into the Devonport dry dock. She did not fight again in this war.