Australia–Japan relations are the bilateral relations between the Commonwealth of Australia and Japan.

Geographically, the two countries are situated in the Asia-Pacific region, with neither country sharing land borders with any other nation. The relationship is generally warm and has continued to grow and strengthen over the years, particularly in relation to defence and security. Both nations are parliamentary constitutional monarchies with close ties to the Western world. Additionally, Australia and Japan are both close allies of the United States, and play an important role in the regional security architecture, as well as the rules-based international order. Both countries are heavily dependent on international trade, with Japan relying on imports of Australian agricultural and energy products, and Australia importing significant quantities of Japanese end-products and consumer goods. Australian troops constituted the majority of Commonwealth Forces which occupied large parts of Japan following the Second World War. In turn, Australia has an extensive history of Japanese influence, with successive waves of immigrants contributing to the social and cultural fabric of modern Australia. Consequently, Australia and Japan have developed a substantial bilateral relationship anchored by mutual interests and reinforced by strong historical, cultural, and people-to-people ties. Today, Japan is Australia's “second largest trading partner and an increasingly important source of capital investment". The relationship continues to expand beyond economic and commercial ties to other spheres, including cultural exchanges, tourism, defence and scientific cooperation.M. Beeson, Bilateral Economic Relations in a Global Political Economy: Australia and Japan

At the beginning of the 20th century, Japan and Australia enjoyed cordial relations, and fought on the same side in the First World War. Early points of contention centred on discrimination against Japanese migrants vis-à-vis the White Australia policy. Japanese expansionism and colonial ambitions further strained relations, with many Australians fearing the possibility of a Japanese invasion. Diplomatic relations were disrupted and considerably damaged by the Second World War; in particular, Japanese air raids on Australia and Japan’s treatment of Australian and allied prisoners of war. Australian suspicion of Japan remained elevated following the re-establishment of diplomatic ties in the early 1950s, and was exacerbated by Japan's perceived economic domination throughout the latter half of the century. However, by the 1980s and early 1990s, Australian government and business leaders had come to see Japan as a vital export market and an essential element in Australia's future growth and prosperity in the Asia-Pacific region. Japan, for its part, regards Australia as an important partner, a reliable source of energy, minerals and other primary products, a popular tourist destination, and the only other middle-ranking economic power in the Asia-Pacific. In 2013, Australia's former Prime Minister Tony Abbott hailed Japan as Australia's closest friend in Asia and proceeded with a free trade agreement (FTA) between the two nations in the following year. Australia and Japan acknowledge one another as key strategic partners in the Asia-Pacific, with both being prosperous liberal democracies and key allies of the United States. Former Defence Minister Marise Payne described Japan as a "key partner" in the region; for his part, Japanese Prime Minister Fumio Kishida described the relationship as the linchpin of security in the Indo-Pacific.

Australia maintains an embassy in Tokyo, and a consulate-general in Osaka. Japan maintains an embassy in Canberra, consulates-general in Sydney, Melbourne, Brisbane, and Perth, along with a consulate in Cairns. Both countries are members of regional groupings such as the Asia-Pacific Economic Cooperation and Comprehensive and Progressive Agreement for Trans-Pacific Partnership.

History Prehistory Anthropologists have noted that Japanese Jomon skulls and the skulls of Ainu people (descendants of the Jomon) shared certain physical traits with Indigenous Australians more than they did with modern East Asians, like the Han Chinese or the later Yayoi Japanese settlers. Fossils found in Okinawa (dated around 20,000 years ago) were theorized to be closely related to Australia’s Keilor remains, suggesting a common ancestor.

Colonial period Between 1635 and 1854, Japanese citizens were in a self-imposed period of isolation from the outside world, which limited their knowledge of it. Australia began appearing on Japanese maps towards the end of the 18th century, which was prior to its colonization by the British. Up until 1794, the Japanese drew Australia as being double its actual size, with New Guinea still attached.Koichiro, M. (2006). Japan and the Pacific, 1540–1920: Threat and Opportunity. United Kingdom: Taylor & Francis. A 1791 Russian map with Australia depicted correctly reached Japan in 1792, and influenced their later maps. This Russian map arrived in Japan through Daikokuya Kōdayū, who came into contact with Russians in 1783, after getting shipwrecked on Amchitka Island in the North Pacific (part of Alaska's Aleutian Islands, then controlled by Russia). Kōdayū lived among Russians and the native Aleuts, who enacted an uprising in 1784, before eventually being returned home to Japan in October 1792.

The first recorded import of Australian coal by Japan occurred in 1865, and the first recorded Japanese imports of Australian wool occurred in 1888. The first Japanese person known to have settled in Australia was a merchant who migrated to Queensland in 1871. By the start of the Australian Federation in 1901, it was estimated that Australia had 4000 Japanese immigrants, mostly based around Townsville where the Japanese government had established its first consulate in 1896. The immigrants worked mostly in the sugar cane and maritime industries including turtle, trochus, trepang and pearl harvesting.Kodansha Encyclopedia, , pp81-82

The Japanese government established a second consulate in Sydney in 1897, which was upgraded to the status of consulate-general in 1902. In the 19th century and early 20th century, the Japanese used the term Nan’yō (South Sea) to refer to Australia and neighboring areas such as Micronesia and Indonesia. By the 1920s, the term evolved into two distinct subgroupings that divided the space into inner and outer parts: the inner or UchiNan’yō referred to the Micronesian island groups encompassing Palau, the Caroline Islands, the Mariana Islands, the Marshall Islands, and the Gilbert Islands; the outer or UraNan’yō took on a wider expanse of territory, extending into the Indonesian archipelago and stretching as far as Australia.Ombrello, M. A. (2014). Monstrous projections and paradisal visions: Japanese conceptualizations of the south seas (nan'yo) as a supernatural space from ancient times to the contemporary period University of Hawai'i. (Order No. 3648583). Available from ProQuest One Academic. (1651935320).

Post-Federation (1901–1941) Following the federation of the Australian colonies in 1901, the new federal government formally enacted the White Australia policy with the aim of barring non-European peoples, including the Japanese, from immigrating to Australia. Hisakichi Eitaki, the Japanese consul in Sydney, lodged a formal protest to Prime Minister Edmund Barton over the proposed Immigration Restriction Act 1901 and asked that Japanese citizens be exempted from the dictation test requirements as "the Japanese belong to an Empire whose standard of civilization is so much higher than that of Kanakas, Negroes, Pacific Islanders, Indians, or other Eastern peoples".

In 1904, the Watson government introduced the so-called "passport agreement", whereby Japanese citizens were exempted from the dictation test if they bore a valid passport specifying the purpose and duration of their visits. This arrangement was similar to the Gentlemen's Agreement of 1907 later established between the United States and Japan. In 1905, the Deakin government passed the Immigration Restriction Amendment Act 1905, which amended the provisions of the dictation test to remove the reference to "any European language" to "any prescribed language". While the amended legislation did not contain any special provisions for Japanese citizens, it was seen as a concession to the Japanese following the Japanese victory in the Russo-Japanese War which reinforced Japan's military equality with European powers. However, this was only a minor concession as it "made no difference to the Commonwealth's basic policy of excluding Japanese permanent settlers from Australia".

Both countries were among the victorious allied powers of World War I. At the Paris Peace Conference, which resulted in the creation of the League of Nations, Australian prime minister Billy Hughes strongly opposed the Japanese government's Racial Equality Proposal. Hughes believed the proposal was a ploy for the Japanese to send migrants to New Guinea (which Australia controlled at the time) as part of their southward expansion efforts. After World War I, the Japanese had gained control of most Micronesian islands from Germany, and Hughes viewed New Guinea as being an important buffer between these areas and Australia.

In 1930–31, Japan was "Australia's third most important trading partner". Economic relations continued to flourish, and by the mid-1930s, Japan had become Australia's second largest export market after the United Kingdom.

Relations with Japan were the primary focus of the Australian Eastern Mission of 1934, a diplomatic tour of East and South-East Asia led by deputy prime minister John Latham. Latham met with Japanese foreign minister Kōki Hirota in May 1934 and covered a range of topics, including the Manchurian question and Japanese readmission to the League of Nations. This meeting marked the first direct interaction between government ministers of the two countries and has been described by one writer as "one of the most important in Australian diplomatic history".

World War II (1941–1945) During World War II, Australian territory was directly threatened by Japanese invasion, and Japanese forces attacked Darwin, Broome, and Sydney Harbour. Australia represented Japan's southernmost region of operation in the Pacific theater, which covered an area of the Pacific Ocean extending as far north as the Aleutian Islands. In 1941, the ethnic Japanese population in Australia was interned, and most were deported to Japan at the end of the war. Australian forces played an active combat role in battles throughout the Southeast Asia and South West Pacific theater of World War II, most notable events of the war among both parties were the Kokoda Track campaign and the Sandakan Death Marches (of which in 2014, the then Japanese Prime Minister Shinzo Abe offered his sincere condolences on behalf of the Japanese people to the Australian Parliament). Australian forces also played a significant role in the post-war Occupation of Japan.

During the Occupation period

The first time a large number of Australians were in Japan was during the postwar Occupation of Japan. Australians were part of the British Commonwealth Occupation Force. Around 16,000 Australians served in the force. For the entire length of its history the BCOF had an Australian officer. The Australian contribution to the force was 4,700 infantry, 5,300 base personnel, 2,200 from the Royal Australian Air Force, and 130 from the Australian General Hospital. The Royal Australian Navy was also present as part of the British Pacific Fleet. For two-thirds of the period of occupation the Commonwealth was represented solely by Australians.