New Guinea campaign in the context of "Independent State of Papua New Guinea"

Papua New Guinea (PNG), officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean north of Australia. It has a land border with Indonesia to the west and maritime borders with Australia to the south and the Solomon Islands to the east. Its capital is Port Moresby. The country's 462,840 km (178,700 sq mi) includes a large mainland and hundreds of islands. The majority of the country's land is held under the collective customary ownership of local clans. This protected tenure is globally exceptional due to remarkable legislative protections granted in PNG’s national constitution.

The territory of Papua New Guinea was split in the 1880s between German New Guinea in the north and the British Territory of Papua in the south, the latter of which was ceded to Australia in 1902. All of present-day Papua New Guinea came under Australian control following World War I, although it remained two distinct territories. The nation was the site of fierce fighting during the New Guinea campaign of World War II, following which the two territories were united in 1949. Papua New Guinea became an independent Commonwealth realm in 1975. Representing the King is a Governor-General. Politics takes place within a Westminster system, with the government led by a Prime Minister. Members of the national parliament also serve as provincial leaders.

The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theater, was the theater of World War II fought between the Japan and the Allies in East and Southeast Asia, the Pacific and Indian Oceans, and Oceania. It was geographically the largest theater of the war, including the Pacific Ocean theater, the South West Pacific theater, the Second Sino-Japanese War, and the brief Soviet–Japanese War, and included some of the largest naval battles in history. War between Japan and the Republic of China had begun in 1937, with hostilities dating back to Japan's invasion of Manchuria in 1931, but the Pacific War is more widely accepted to have begun in 1941, when the United States and United Kingdom were brought into the war, after being attacked by Japan.

Japan invaded French Indochina in 1940, and extended its control over the entire territory in July 1941. On 7–8 December 1941, Japan attacked the American naval base at Pearl Harbor in Hawaii; the U.S.-held Philippines, Guam, and Wake Island; and the British colonies of Malaya, Singapore, and Hong Kong, followed by a Japanese declaration of war. The Japanese achieved great success over the next 6 months, allying with Thailand and capturing the listed territories (except for Hawaii) in addition to Borneo, New Britain, the Dutch East Indies, Burma, the Solomon and Gilbert Islands, and parts of New Guinea. In May 1942, Japanese and Allied aircraft carriers fought at the Battle of Coral Sea, resulting in the retreat of a Japanese invasion force headed for Port Moresby. In June, Japan invaded the Aleutian Islands, and in the central Pacific was defeated at the Battle of Midway, considered a key turning point in the war. After this point, the Japanese experienced great difficulty replacing their losses in ships and aircraft as the U.S. produced ever increasing numbers of both.

The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theater, was the theater of World War II fought between Japan and the Allies in East and Southeast Asia, the Pacific and Indian Oceans, and Oceania. It was geographically the largest theater of the war, including the Pacific Ocean theater, the South West Pacific theater, the Second Sino-Japanese War, and the brief Soviet–Japanese War, and included some of the largest naval battles in history. War between Japan and the Republic of China had begun in 1937, with hostilities dating back to Japan's invasion of Manchuria in 1931, but the Pacific War is more widely accepted to have begun in 1941, when the United States and United Kingdom were brought into the war, after being attacked by Japan.

Japan invaded French Indochina in 1940, and extended its control over the entire territory in July 1941. On 7–8 December 1941, Japan attacked the American naval base at Pearl Harbor in Hawaii; the U.S.-held Philippines, Guam, and Wake Island; and the British colonies of Malaya, Singapore, and Hong Kong, followed by a Japanese declaration of war. The Japanese achieved great success over the next 6 months, allying with Thailand and capturing the listed territories (except for Hawaii) in addition to Borneo, New Britain, the Dutch East Indies, Burma, the Solomon and Gilbert Islands, and parts of New Guinea. In May 1942, Japanese and Allied aircraft carriers fought at the Battle of Coral Sea, resulting in the retreat of a Japanese invasion force headed for Port Moresby. In June, Japan invaded the Aleutian Islands, and in the central Pacific was defeated at the Battle of Midway, considered a key turning point in the war. After this point, the Japanese experienced great difficulty replacing their losses in ships and aircraft as the U.S. produced ever increasing numbers of both.

The Admiralty Islands campaign (Operation Brewer) was a series of battles in the New Guinea campaign of World War II in which the United States Army's 1st Cavalry Division took the Japanese-held Admiralty Islands.

Acting on reports from airmen that there were no signs of enemy activity and the islands might have been evacuated, General Douglas MacArthur accelerated his timetable for capturing the Admiralties and ordered an immediate reconnaissance in force. The campaign began on 29 February 1944 when a force landed on Los Negros, the third-largest island in the group. By using a small, isolated beach where the Japanese had not anticipated an assault, the force achieved tactical surprise, but the islands proved to be far from unoccupied. A furious battle over the islands ensued.