Empire of Japan in the context of "Harbin"

World War II or the Second World War (1 September 1939 – 2 September 1945) was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks and aircraft played major roles, enabling the strategic bombing of cities and delivery of the first and only nuclear weapons ever used in war. World War II is the deadliest conflict in history, causing the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were put on trial for war crimes.

The causes of World War II included unresolved tensions in the aftermath of World War I, the rise of fascism in Europe and militarism in Japan. Key events preceding the war included Japan's invasion of Manchuria in 1931, the Spanish Civil War, the outbreak of the Second Sino-Japanese War in 1937, and Germany's annexations of Austria and the Sudetenland. World War II is generally considered to have begun on 1 September 1939, when Nazi Germany, under Adolf Hitler, invaded Poland, after which the United Kingdom and France declared war on Germany. Poland was divided between Germany and the Soviet Union under the Molotov–Ribbentrop Pact. In 1940, the Soviet Union annexed the Baltic states and parts of Finland and Romania. After the fall of France in June 1940, the war continued mainly between Germany, now assisted by Fascist Italy, and the British Empire, with fighting in the Balkans, Mediterranean, and Middle East, the aerial Battle of Britain and the Blitz, and the naval Battle of the Atlantic. Through campaigns and treaties, Germany gained control of much of continental Europe and formed the Axis alliance with Italy, Japan, and other countries. In June 1941, Germany invaded the Soviet Union, opening the Eastern Front and initially making large territorial gains.

Bakumatsu (幕末; Japanese pronunciation: [ba.kɯ.ma.tsɯ], 'end of the bakufu') were the final years of the Edo period when the Tokugawa shogunate ended. Between 1853 and 1867, under foreign diplomatic and military pressure, Japan ended its isolationist foreign policy known as sakoku and changed from a feudal Tokugawa shogunate to the modern empire of the Meiji government. The major ideological-political divide during this period was between the pro-imperial nationalists called ishin shishi and the shogunate forces, which included the elite shinsengumi swordsmen.

Although these two groups were the most visible powers, many other factions attempted to use the chaos of bakumatsu to seize personal power. Furthermore, there were two other main driving forces for dissent: first, growing resentment on the part of the tozama daimyō (or outside lords), and second, growing anti-Western sentiment following the arrival of Matthew C. Perry. The first related to those lords whose predecessors had fought against Tokugawa forces at the Battle of Sekigahara in 1600, after which they had been permanently excluded from all powerful positions within the shogunate. The second was to be expressed in the phrase sonnō jōi, or "revere the Emperor, expel the barbarians". The turning point of the Bakumatsu was during the Boshin War and the Battle of Toba–Fushimi when pro-shogunate forces were defeated.

Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main island of Taiwan, also known as Formosa, lies between the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. It has an area of 35,808 square kilometres (13,826 square miles), with mountain ranges dominating the eastern two-thirds and plains in the western third, where its highly urbanized population is concentrated. The combined territories under ROC control consist of 168 islands in total covering 36,193 square kilometres (13,974 square miles). The largest metropolitan area is formed by Taipei (the capital), New Taipei City, and Keelung. With around 23.9 million inhabitants, Taiwan is among the most densely populated countries.

Taiwan has been settled for at least 25,000 years. Ancestors of Taiwanese indigenous peoples settled the island around 6,000 years ago. In the 17th century, large-scale Han Chinese immigration began under Dutch colonial rule and continued under the Kingdom of Tungning, the first predominantly Han Chinese state in Taiwanese history. The island was annexed in 1683 by the Qing dynasty and ceded to the Empire of Japan in 1895. The Republic of China, which had overthrown the Qing in 1912 under the leadership of Sun Yat-sen, assumed control following the surrender of Japan in World War II. But with the loss of mainland China to the Communists in the Chinese Civil War, the government moved to Taiwan in 1949 under the Kuomintang (KMT).

Seoul, officially Seoul Special Metropolitan City, is both the capital and largest city of South Korea, and the largest city in the whole of Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's sixth largest metropolitan economy in 2022, behind New York, Tokyo, Los Angeles, Paris, and London, and hosts more than half of South Korea's population. Although Seoul's population peaked at over 10 million, it has gradually decreased since 2014, standing at about 9.6 million residents as of 2024. Seoul is the seat of the South Korean government.

Seoul's history traces back to 18 BC when it was founded by the people of Baekje, one of the Three Kingdoms of Korea. During the Joseon dynasty, Seoul was officially designated as the capital, surrounded by the Fortress Wall of Seoul. In the early 20th century, Seoul was occupied by the Empire of Japan, temporarily renamed "Keijō" ("Gyeongseong" in Korean). The Korean War brought fierce battles, with Seoul changing hands four times and leaving the city mostly in ruins. Nevertheless, the city has since undergone significant reconstruction and rapid urbanization.

The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States also asserts sovereignty over five major island territories and various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's third-largest land area and third-largest population, exceeding 340 million.

Paleo-Indians first migrated from North Asia to North America over 12,000 years ago, and formed various civilizations. Spanish colonization established Spanish Florida in 1513, the first European colony in what is now the continental United States. British colonization followed with the 1607 settlement of Virginia, the first of the Thirteen Colonies. Enslavement of Africans was practiced in all colonies by 1770 and supplied most of the labor for the Southern Colonies' plantation economy. Clashes with the British Crown over taxation and lack of parliamentary representation sparked the American Revolution, leading to the Declaration of Independence on July 4, 1776. Victory in the 1775–1783 Revolutionary War brought international recognition of U.S. sovereignty and fueled westward expansion, dispossessing native inhabitants. As more states were admitted, a North–South division over slavery led the Confederate States of America to attempt secession and fight the Union in the 1861–1865 American Civil War. With the United States' victory and reunification, slavery was abolished nationally. By 1900, the country had established itself as a great power, a status solidified after its involvement in World War I. Following Japan's attack on Pearl Harbor in 1941, the U.S. entered World War II. Its aftermath left the U.S. and the Soviet Union as rival superpowers, competing for ideological dominance and international influence during the Cold War. The Soviet Union's collapse in 1991 ended the Cold War, leaving the U.S. as the world's sole superpower.

An empire is a realm controlled by an emperor or an empress and divided between a dominant center and subordinate peripheries. The center of the empire (sometimes referred to as the metropole) has political control over the peripheries. Within an empire, different populations may have different sets of rights and may be governed differently. The word "empire" derives from the Roman concept of imperium. Narrowly defined, an empire is a sovereign state whose head of state uses the title of "emperor" or "empress"; but not all states with aggregate territory under the rule of supreme authorities are called "empires" or are ruled by an emperor; nor have all self-described empires been accepted as such by contemporaries and historians (the Central African Empire of 1976 to 1979, and some Anglo-Saxon kingdoms in early England being examples).

There have been "ancient and modern, centralized and decentralized, ultra-brutal and relatively benign" empires. An important distinction has been between land empires made up solely of contiguous territories, such as the Achaemenid Empire, Roman Empire, the Mongol Empire, or the Russian Empire; and those - based on sea-power - which include territories that are remote from the 'home' country of the empire, such as the Dutch colonial empire, the Empire of Japan, the Chola Empire or the British Empire.

The Axis powers, originally called the Rome–Berlin Axis and also Rome–Berlin–Tokyo Axis, was the military coalition which initiated World War II and fought against the Allies. Its principal members were Nazi Germany, the Kingdom of Italy and the Empire of Japan. The Axis were united in their far-right positions and general opposition to the Allies, but otherwise lacked comparable coordination and ideological cohesion.

The Axis grew out of successive diplomatic efforts by Germany, Italy, and Japan to secure their own specific expansionist interests in the mid-1930s. The first step was the protocol signed by Germany and Italy in October 1936, after which Italian leader Benito Mussolini declared that all other European countries would thereafter rotate on the Rome–Berlin axis, thus creating the term "Axis". The following November saw the ratification of the Anti-Comintern Pact, an anti-communist treaty between Germany and Japan; Italy joined the Pact in 1937, followed by Hungary and Spain in 1939. The "Rome–Berlin Axis" became a military alliance in 1939 under the so-called "Pact of Steel", with the Tripartite Pact of 1940 formally integrating the military aims of Germany, Italy, Japan, and later followed by other nations. The three pacts formed the foundation of the Axis alliance.

Almost every country in the world participated in World War II. Most were neutral at the beginning, but relatively few nations remained neutral to the end. World War II pitted two alliances against each other, the Allies and the Axis powers. It is estimated that 74 million people died, with estimates ranging from 40 million to 90 million dead (including all genocide casualties). The main Axis powers were Nazi Germany, the Empire of Japan, and the Kingdom of Italy; while the United Kingdom, the United States, the Soviet Union and China were the "Big Four" Allied powers.

The countries involved in or affected by World War II are listed alphabetically, with a description of their role in the conflict.

Air warfare was a major component in all theaters of World War II and, together with anti-aircraft warfare, consumed a large fraction of the industrial output of the major powers. Germany and Japan depended on air forces that were closely integrated with land and naval forces; the Axis powers downplayed the advantage of fleets of strategic bombers and were late in appreciating the need to defend against Allied strategic bombing. By contrast, Britain and the United States took an approach that greatly emphasized strategic bombing and (to a lesser degree) tactical control of the battlefield by air as well as adequate air defenses. Both Britain and the U.S. built substantially larger strategic forces of large, long-range bombers. Simultaneously, they built tactical air forces that could win air superiority over the battlefields, thereby giving vital assistance to ground troops. The U.S. Navy and Royal Navy also built a powerful naval-air component based on aircraft carriers, as did the Imperial Japanese Navy; these played the central role in the war at sea.

Japan was occupied and administered by the Allies of World War II from the surrender of the Empire of Japan on September 2, 1945, at the war's end until the Treaty of San Francisco took effect on April 28, 1952. The occupation, led by the American military with support from the British Commonwealth and under the supervision of the Far Eastern Commission, involved a total of nearly one million Allied soldiers. The occupation was overseen by the US General Douglas MacArthur, who was appointed Supreme Commander for the Allied Powers by the US president Harry S. Truman; MacArthur was succeeded as supreme commander by General Matthew Ridgway in 1951. Unlike in the occupations of Germany and Austria, the Soviet Union had little to no influence in Japan, declining to participate because it did not want to place Soviet troops under MacArthur's direct command.

This foreign presence marks the only time in the history of Japan that it has been occupied by a foreign power. However, unlike in Germany, the Allies never assumed direct control over Japan's civil administration. In the immediate aftermath of Japan's military surrender, the country's government continued to formally operate under the provisions of the Meiji Constitution.