I Marine Amphibious Corps or IMAC was created on 1 October 1942 and deployed to the South Pacific

South Pacific Area

The South Pacific Area was a multinational U.S.-led military command active during World War II. It was a part of the U.S. Pacific Ocean Areas under Admiral Chester Nimitz.Instructions to the senior U.S...

, first to Hawaii, then to New Caledonia

New Caledonia

New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

. When the Marine Corps was not satisfied with the leadership of its commander, Major General Clayton Vogel, Commandant

Commandant of the Marine Corps

The Commandant of the Marine Corps is normally the highest ranking officer in the United States Marine Corps and is a member of the Joint Chiefs of Staff...

 Thomas Holcomb

Thomas Holcomb

General Thomas Holcomb was the seventeenth Commandant of the United States Marine Corps . He was the first Marine to achieve the rank of General. After retiring from the Marine Corps, Holcomb served as Minister to South Africa .-Early years:Holcomb was born on August 5, 1879 in New Castle, Delaware...

 ordered Alexander Vandegrift

Alexander Vandegrift

Alexander Archer Vandegrift, KBE, CB was a General in the United States Marine Corps. He commanded the 1st Marine Division to victory in its first ground offensive of World War II — Battle of Guadalcanal. For his actions during the Solomon Islands campaign, he received the Medal of Honor...

 to take command. Vandegrift, the commander of the 1st Marine Division during the Battle of Guadalcanal

Guadalcanal campaign

The Guadalcanal Campaign, also known as the Battle of Guadalcanal and codenamed Operation Watchtower by Allied forces, was a military campaign fought between August 7, 1942 and February 9, 1943 on and around the island of Guadalcanal in the Pacific theatre of World War II...

 was promoted to Lt. General.

General Vandegrift carried on in command of the Corps when its next designated commander for the invasion of Bougainville, Major General Charles Barrett died when he fell from the balcony of his quarters in New Caledonia

New Caledonia

New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

. General Vandegrift led IMAC during the invasion and was later made the Commandant.

On 15 April 1944 IMAC was renamed the III Amphibious Corps

III Marine Expeditionary Force

The III Marine Expeditionary Force is a Marine Air-Ground Task Force of the United States Marine Corps that is forward-deployed and able to deploy rapidly and conduct operations across the spectrum from humanitarian assistance and disaster relief to amphibious assault and high intensity combat. III...

.

Commanders

• Clayton B. Vogel 1 October 1942 – July 1943
• Charles D. Barrett
  Charles D. Barrett
  Major General Charles Dodson Barrett was the first Commanding General of the 3rd Marine Division. He was killed accidentally while on duty in the South Pacific, 8 October 1943. He was posthumously awarded the Distinguished Service Medal in recognition of his outstanding service during World War...
  
   27 September 1943 – 8 October 1943 (Died from a fall)
• Alexander Vandegrift
  Alexander Vandegrift
  Alexander Archer Vandegrift, KBE, CB was a General in the United States Marine Corps. He commanded the 1st Marine Division to victory in its first ground offensive of World War II — Battle of Guadalcanal. For his actions during the Solomon Islands campaign, he received the Medal of Honor...
  
  July 1943 – 27 September 1943 and 8 October 1943 – 1 November 1943