On 12 July 1944, he assumed command of the Fifth Amphibious Corps and led that command in the assault and capture of Tinian Island. He was awarded a Distinguished Service Medal and a Gold Star in lieu of a second Distinguished Service Medal for exceptional meritorious service in the seizure and occupation of the Marshall Islands and in the assault and capture of Saipan and Tinian. Schmidt commanded the Fifth Amphibious Corps through the Iwo Jima operation and was awarded a second Gold Star in lieu of a third Distinguished Service Medal for his part in this operation. His citation reads in part, "Against determined enemy resistance and incomparable natural defenses, Major General Schmidt skillfully directed the attack of his troops to capture and occupy this strategic island. He handled the various units under his command with brilliant tactical skill. His sound judgment, distinctive administrative ability and unfailing devotion to duty were vital factors in the success of the entire operation." Following the conclusion of hostilities, he led the Fifth Amphibious Corps in the occupation of the Japanese Home Islands.