'Cheekstrap' was the US geographical rather than operational designation for New Caledonia island in the French-colonised New Hebrides islands group of the south-western Pacific Ocean (1941/45).

New Caledonia is a large island, some 248 miles (400 km) long and 31 miles (50 km) wide with a total land area of 7,056 sq miles (18275 km²). The island lies about 900 miles (1450 km) to the north-east of Brisbane in eastern Australia. Two rugged mountain chains, of which the larger is the Chaine Centrale, extend the length of the island: the mountains reach to a height of more than 5,000 ft (1525 m) and produce a rain shadow in the interior plateau and on the south-western coast, leaving these areas sparsely vegetated. There is a barrier reef, the second largest in the world, which is some 995 miles (1600 km) in length around the island and creates the world’s largest lagoon to the north-west of the island. The reef also produces a deep protected channel along the south-western coast, and this is much used by coastal vessels. Located well to the south of the equator, the island has a pleasant climate, similar to that of the Hawaiian islands group, and possess an excellent harbour at Nouméa in the south-east.

The island has major deposits of nickel and chromium. The former were discovered in 1863, and the French subsequently set up penal colonies which supplied labour for the mines over a period of four decades, but fewer than 100 convicts were left by 1942. New Caledonia supplied 20% of the world’s nickel in 1941. In addition to metal ores, the island produced tropical fruit and timber, and had a substantial meat and fish canning industry.

The native population of about 70,000 persons was split into a land-owning class which generally worked with the French, and mountain tribes which were suspected of continued cannibalism and kept under close watch by the French gendarmerie. The island also had about 8,000 indentured labourers from French Indo-China and Dutch Java, as well as about 17,000 Europeans. In 1935 the Japanese had reached agreement with the French to mine nickel and iron on the island, and several hundred Japanese civilians were interned at Goro near the south-eastern end of the island after the outbreak of war.

The island had a good road, Route Coloniale Nr 1, which extended from Nouméa along the entire south-western coast and partway around the north-eastern coast, three roads crossed the island to connect the coasts, and a narrow-gauge railway linked Nouméa and Paita, some 20 miles (32 km) to the capital’s north-west. The entire island had a well-developed telegraph system and there was a modern telephone exchange in Nouméa.

New Caledonia was a French colony and controlled by the Free French during the Pacific War. The political situation was distinctly tense when war broke out in the Pacific, however, and Général de Brigade Charles de Gaulle, leader of the Free French movement, sent Contre-amiral Georges Thierry d’Argenlieu to the island early in 1942 to replace a popular governor whose loyalty was suspect: there was enough pro-Axis feeling among the islanders. however, that counter-revolution became a possibility.

On the outbreak of the Pacific War, the French garrison of New Caledonia comprised one 800-man battalion, which was rapidly supplemented by a 2,000-man home guard formation and a 300-man company of Australian troops, but this was wholly inadequate to ensure the retention of an island which was so large and valuable. The Free French at one time considered ending the Australian construction of a large airfield in the hope that this would make the island less attractive to the Japanese, who had already made plans for Major General Tomitaro Horii’s South Seas Detachment to move on the island.

A garrison of about 16,800 US troops, centred on the 51^st Brigade and the 70^th Coast Artillery (Anti-Aircraft), was organised into Task Force 6814 and reached at the island on 12 March 1942. Here the task force was joined by the 67^th Fighter Squadron. The troops on New Caledonia later constituted the core of the Americal Division, the first part of the title being a contraction of 'Americans on New Caledonia'.

Numerous airfields were then built around the island, The most important of these were Tontouta, some 33 miles (53 km) to the north of Nouméa and which had two runways when war broke out, and Oua Tom to the north of Tontouta, which had a single runway. A third airfield at Koumac at the north-western end of the island was destroyed to prevent its possible use by the Japanese, but was later rebuilt by the US Army. Another airfield was under construction at Plaine de Gaics, and seven auxiliary airstrips were built during the war.

Nouméa became the headquarters of the US Army and US Navy forces in the South Pacific Area, and the island (later known as 'Iret') was strongly held primarily to deny it to the Japanese, but also proved of major importance as a support base for the 'Watchtower' campaign on Guadalcanal.