Shelling of Port Gregory

On 28 January 1943, the Japanese submarine I-165 under the command of Tatenosuke Tosu arrived at a position of about 7 km off the small town of Port Gregory in Western Australia. Commander Tatenosuke fired approximately 10 shells towards Port Gregory, causing no damage. While the bombardment was spotted by Australian coast-watchers, Allied naval authorities only learned of the attack when the submarine's battle report radio signal was intercepted and decoded a week later.

The purpose of this attack was to draw the Allied attention away from the evacuation of Guadalcanal.

The attack on Port Gregory was one of three submarine shellings on Australian cities, the other two being Newcastle and Sydney.