Amur Annexation in the context of "Amur Oblast"

Northeast China (Chinese: 东北; pinyin: Dōngběi) is a geographical region of China, consisting officially of three provinces Liaoning, Jilin and Heilongjiang. The heartland of the region is the Northeast China Plain, the largest plain in China with an area of over 350,000 km (140,000 sq mi). The region is separated from the Russian Far East to the north and east by the Amur, Argun and Ussuri Rivers; from North Korea to the south by the Yalu and Tumen Rivers; and from the neighboring North China to the west by the Greater Khingan Range and Yan Mountains. It is also bounded by the Bohai Bay and Yellow Sea to the southwest, about 100 km (62 mi) away from East China's Jiaodong Peninsula across the Bohai Strait, due to be connected via a proposed undersea tunnel.

The four prefectures of Inner Mongolia (which is part of North China) east of the Greater Khingan, i.e. Chifeng, Tongliao, Hinggan and Hulunbuir, are sometimes also considered broader parts of Northeast China, and together with the aforementioned three provinces formed what was historically known as Inner Manchuria, in contrast to the Outer Manchuria (or "Outer Northeast" in Chinese literatures) annexed by the Russian Empire during the mid-19th century.

Outer Manchuria, sometimes called Russian Manchuria, refers to a region in Northeast Asia that is now part of the Russian Far East but historically formed part of Manchuria (until the mid-19th century). While Manchuria now more normatively refers to Northeast China, it originally included areas consisting of Priamurye between the left bank of Amur River and the Stanovoy Range to the north, and Primorskaya which covered the area in the right bank of both Ussuri River and the lower Amur River to the Pacific Coast. The region was ruled by a series of Chinese dynasties and the Mongol Empire, but control of the area was ceded to the Russian Empire by Qing China during the Amur Annexation in the 1858 Treaty of Aigun and 1860 Treaty of Peking, with the terms "Outer Manchuria" and "Russian Manchuria" arising after the Russian annexation.

Prior to its annexation by Russia, Outer Manchuria was predominantly inhabited by various Tungusic peoples who were categorized by the Han Chinese as "Wild Jurchens". The Evenks, who speak a closely related Tungusic language to Manchu, make up a significant part of the indigenous population today. When the region was a part of the Qing dynasty, a small population of Han Chinese men migrated to Outer Manchuria and married the local Tungusic women. Their mixed descendants would emerge as a distinct ethnic group known as the Taz people.

Manchuria is a historical region in northeast Asia encompassing the entirety of present-day northeast China and parts of the modern-day Russian Far East south of the Uda River and the Tukuringra-Dzhagdy Ranges. The exact geographical extent varies depending on the definition: in the narrow sense, the area constituted by three Chinese provinces of Heilongjiang, Jilin, and Liaoning as well as the eastern Inner Mongolian prefectures of Hulunbuir, Hinggan, Tongliao, and Chifeng; in a broader sense, historical Manchuria includes those regions plus the Amur river basin, parts of which were ceded to the Russian Empire by the Manchu-led Qing dynasty during the Amur Annexation of 1858–1860. The parts of Manchuria ceded to Russia are collectively known as Outer Manchuria or Russian Manchuria, which include present-day Amur Oblast, Primorsky Krai, the Jewish Autonomous Oblast, the southern part of Khabarovsk Krai, and the eastern edge of Zabaykalsky Krai.

The name Manchuria is an exonym (derived from the endonym "Manchu") of Japanese origin. The history of "Manchuria" (Manzhou) as a toponym in China is disputed, with some scholars believing it was never used while others believe it was by the late 19th century. The area was historically referred to by various names in the Qing dynasty such as Guandong (East of the Pass) or the Three Provinces referring to Fengtian (Liaoning), Heilongjiang, and Jilin. Manchuria as a geographical term was first used in the 18th or 19th centuries by the Japanese before spreading to Europe. The term was promoted by the Empire of Japan in support for the existence of its puppet state, Manchukuo. Although the toponym is still used, some scholars treat the term with caution or avoid it altogether due to its association with Japanese colonialism. The term is deprecated in China due to its association with Japanese imperialism and ethnic connotations. As a result, areas once considered part of Manchuria are simply referred to as the Northeast. The Three Provinces and the Northeast were also in concurrent use among the Japanese along with Manchuria until the Mukden incident of 1931.

Vladivostok (/ˌvlædɪˈvɒstɒk/ VLAD-iv-OST-ok; Russian: Владивосток, lit. '"Ruler of the East"', IPA: [vlədʲɪvɐˈstok] ) is the largest city and the administrative center of Primorsky Krai and the capital of the Far Eastern Federal District of Russia. It is located around the Golden Horn Bay on the Sea of Japan, covering an area of 331.16 square kilometers (127.86 square miles), with a population of 603,519 residents as of 2021. Vladivostok is the second-largest city in the Far Eastern Federal District, as well as the Russian Far East, after Khabarovsk. It is located approximately 45 kilometers (28 mi) from the China–Russia border and 134 kilometers (83 mi) from the North Korea–Russia border.

Vladivostok was historically part of Outer Manchuria. Shortly after the signing of the Treaty of Aigun between Qing China and the Russian Empire and affirmed by the Convention of Peking – from which it is also known as the Amur Annexation – the city was founded as a Russian military outpost on July 2, 1860. In 1872, the main Russian naval base on the Pacific Ocean was transferred to the city, stimulating its growth. In 1914 the city experienced rapid growth economically and ethnically diverse with population exceeding over 100,000 inhabitants with slightly less than half of the population being Russians. During this time, large Asian communities developed in the city. The public life of the city flourished; many public associations were created, from charities to hobby groups. After the outbreak of the Russian Revolution in 1917, Vladivostok was occupied in 1918 by White Russian and Allied forces, the last of whom, from the Japanese Empire, were not withdrawn until 1922 as part of its wider intervention in Siberia; by that time the antirevolutionary White Army forces had collapsed. That same year, the Red Army occupied the city, absorbing the Far Eastern Republic into the Russian Soviet Federative Socialist Republic. Following the dissolution of the Soviet Union in 1991, the city became a part of the Russian Federation.

The Treaty of Nerchinsk of 1689 was the first treaty between the Tsardom of Russia and the Qing dynasty of China after the defeat of Russia by Qing China at the Siege of Albazin in 1686. The Russians gave up the area north of the Amur River as far as the Stanovoy Range and kept the area between the Argun River and Lake Baikal. This border along the Argun River and Stanovoy Range lasted until the Amur Annexation via the Treaty of Aigun in 1858 and the Convention of Peking in 1860. It opened markets for Russian goods in China, and gave Russians access to Chinese supplies and luxuries.

The agreement was signed in Nerchinsk on 27 August 1689. The signatories were Songgotu on behalf of the Kangxi Emperor and Fyodor Golovin on behalf of the Russian tsars Peter I and Ivan V.

Manchuria under Qing rule was the rule of the Qing dynasty of China (and its predecessor the Later Jin dynasty) over the greater region of Manchuria, including today's Northeast China and Outer Manchuria, although Outer Manchuria was lost to the Russian Empire after the Amur Annexation. The Qing dynasty itself was established by the Manchus, a Tungusic people from Manchuria, who later replaced the Ming dynasty as the ruling dynasty of China. Thus, the region is often seen to have had a special status during the Qing and was not governed as regular provinces until the late Qing dynasty, although the name "Manchuria" itself is an exonym of Japanese origin and was not used by the Qing dynasty in Chinese or Manchu.

Count Nikolay Nikolayevich Muravyov-Amursky (Russian: Никола́й Никола́евич Муравьёв-Аму́рский; August 23 [O.S. August 11] 1809 – November 30 [O.S. November 18] 1881) was a Russian general, statesman and diplomat, who played a major role in the expansion of the Russian Empire into the Amur River basin and to the shores of the Sea of Japan.