On the Eastern Front… Soviet forces conduct a successful amphibious assault on Mariupol, on the coast of the Sea of Azov. In the Caucasus, a similar landing in the Kuban Peninsula at Novorossiysk meets heavy resistance. In the Donets basin, Soviet forces capture Barvenkovo, Volnovakha and Chaplino.

In Italy… On the Salerno beachhead, the forces of the American 6th Corps advance inland. The forces of the British 10th Corps occupy Montecorvino airfield and Battipaglia. German counterattacks by local divisional forces recapture the British gains before nightfall. German forces south of the beachhead, including those engaging the British 8th Army, withdraw northward to reinforce the forces containing the Allied beachhead at Salerno. Rearguard forces continue resisting Montgomery's forces.

In the Mediterranean… The Italian fleet, including 5 battleships, arrives in Malta to surrender. Many smaller Italian vessels reach other Allied ports. The island of Castelrosso, in the Aegean Sea, is occupied by British troops. Two British officers are parachuted on to the island of Rhodes to contact the Italian garrison commander, General Campione, about surrendering. Meanwhile, the German garrison on Sardinia begins evacuating to Corsica in transit to the Italian mainland. This operation is completed by September 30th.

In New Guinea… The Australian 7th Division begins advancing from its positions at Nadzab toward Lae. Patrols reach Heath's Plantation.

In the Solomon Islands… There is heavy fighting on Arundel island. More American reinforcements are sent to the island.