Kwantung Leased Territory in the context of "Triple Intervention"

The Empire of Japan, also known as the Japanese Empire or Imperial Japan, was the Japanese nation state that existed from the Meiji Restoration on January 3, 1868, until the Constitution of Japan took effect on May 3, 1947. From August 1910 to September 1945, it included the Japanese archipelago, the Kurils, Karafuto, Korea, and Taiwan. The South Seas Mandate and concessions such as the Kwantung Leased Territory were de jure not internal parts of the empire but dependent territories. In the closing stages of World War II, with Japan defeated alongside the rest of the Axis powers, the formalized surrender was issued on September 2, 1945, in compliance with the Potsdam Declaration of the Allies, and the empire's territory subsequently shrunk to cover only the Japanese archipelago resembling modern Japan.

Under the slogans of "Enrich the Country, Strengthen the Armed Forces" and "Promote Industry" which followed the Boshin War and the restoration of power to the emperor from the shogun, Japan underwent a period of large-scale industrialization and militarization, often regarded as the fastest modernization of any country to date. All of these aspects contributed to Japan's emergence as a great power following the First Sino-Japanese War, the Boxer Rebellion, the Russo-Japanese War, and World War I. Economic and political turmoil in the 1920s, including the Great Depression, led to the rise of militarism, nationalism, statism and authoritarianism, during which Japan joined the Axis alliance with Nazi Germany and Fascist Italy, conquering a large part of the Asia–Pacific; during this period, the Imperial Japanese Army (IJA) and the Imperial Japanese Navy (IJN) committed numerous atrocities and war crimes, including the Nanjing Massacre. There has been a debate over defining the political system of Japan as a dictatorship, which has been disputed due by the absence of a dictator, and over calling it fascist. The other suggested terms were para-fascism, militarism, corporatism, totalitarianism, and police state.

The Treaty of Shimonoseki (Japanese: 下関条約, Hepburn: Shimonoseki Jōyaku), also known as the Treaty of Maguan in China or the Treaty of Bakan (馬關條約, Bakan Jōyaku) in Japan, was signed in Shimonoseki, Japan, on April 17, 1895, between the Empire of Japan and the Qing dynasty. The treaty ended the First Sino-Japanese War, in which the Japanese decisively defeated the Chinese land and naval forces. The treaty was signed at the Shunpanrō [ja] hotel by Count Itō Hirobumi and Viscount Mutsu Munemitsu for Japan and Li Hongzhang and his son Li Jingfang on behalf of China.

The peace conference took place from March 20 to April 17, 1895, and the treaty followed and superseded the Sino-Japanese Friendship and Trade Treaty of 1871. It consisted of 11 articles which provided for the termination of China's tributary relations with Korea; required that China pay an indemnity of 200 million taels and cede Taiwan (Formosa), the Penghu (Pescadores) Islands, and the Liaodong Peninsula to Japan; and opened four cities (Shashi, Chongqing, Suzhou, and Hangzhou) to Japan as trading ports. However, due to the diplomatic Triple Intervention of Russia, Germany, and France just one week after the treaty was signed, the Japanese withdrew their claim to the Liaodong Peninsula in return for an additional war indemnity of 30 million taels from China.

The Kwantung Army (Japanese: 関東軍, Kantō-gun) was a general army of the Imperial Japanese Army from 1919 to 1945.

The Kwantung Army was formed in 1906 as a security force for the Kwantung Leased Territory and South Manchurian Railway Zone after the Russo-Japanese War of 1904–1905 and expanded into an army group during the interwar period to support Japanese interests in China, Manchuria, and Mongolia. The Kwantung Army became the most prestigious command in the Imperial Japanese Army, and many of its personnel won promotions to high positions in the Japanese military and civil government, including Hideki Tojo and Seishirō Itagaki. The Kwantung Army was largely responsible for the establishment and proxy control of the Japanese puppet-state of Manchukuo in Manchuria and functioned as one of the main Japanese fighting forces during the 1937–1945 Second Sino-Japanese War.

"Mainland Japan" (内地, naichi; lit. '"inner lands"') is a term used to distinguish Japan's core land area from its outlying territories. "Mainland Japan" was an official term in the pre-war period, distinguishing Japan proper from its overseas territories (外地, gaichi, lit. "outer lands") in the Far East, such as Japanese Taiwan, Japanese Korea, Karafuto, the South Seas Mandate, and the Kwantung Leased Territory. After the end of World War II, its usage became less common and lost its previous legal significance.

The term's literal Japanese meaning might best be translated as "inner Japan" or "inner lands". The term "mainland" is somewhat inaccurate since it usually refers to all or part of a continental landmass, rather than islands. In the pre-1945 period, the "inner lands" included the Japanese archipelago, itself including the Ryukyu Islands and other island chains to the south of Honshu. The "inner lands" also referred during 1875–1945 to the Japanese-controlled Kuril Islands and during 1943–1945 to Karafuto, the southern half of the island of Sakhalin.

The Treaty of Portsmouth is a treaty that formally ended the 1904–1905 Russo-Japanese War. It was signed on September 5, 1905, after negotiations from August 6 to 30, at the Portsmouth Naval Shipyard in Kittery, Maine, United States. U.S. President Theodore Roosevelt was instrumental in the negotiations and won the Nobel Peace Prize for his efforts, the first ever American recipient. The treaty recognized Japan's hegemony in Korea (which soon after became a protectorate of the Empire of Japan), awarded it Russia's lease on the Liaodong Peninsula (which became the Kwantung Leased Territory), control of the Russian-built South Manchuria Railway, and the southern half of the island of Sakhalin (Karafuto).