The Amur Annexation was the annexation of territories adjoining the Amur River by the Russian Empire in 1858–1860 through unequal treaties forced upon the Chinese Qing dynasty. The 1858 Treaty of Aigun signed between the Russian general Muraviev and the Chinese official Yishan ceded Priamurye, a territory stretching from the Amur River in the south to the Stanovoy Mountains in the north, but the Qing government refused to recognize the validity of the treaty at the time. Two years later, the Second Opium War concluded with the Convention of Peking, which affirmed Russian gains under the Treaty of Aigun and China also ceded Primorye, a territory that included the entire Pacific coast down to the Korean border, as well as the island of Sakhalin. These territories roughly correspond to modern-day Amur Oblast and Primorsky Krai, respectively. Collectively, they are often referred to as Outer Manchuria, part of the greater region of Manchuria.
Background
Hydrologically, the Stanovoy Range separates the rivers that flow north into the Arctic from those that flow south into the Amur River. Ecologically, the area is the southeastern edge of the Siberian boreal forest with some areas good for agriculture along the middle Amur. Socially and politically, from about 600 CE, it was the northern fringe of the Chinese-Korean-Manchu world.
In 1643, Russian adventurers spilled over the Stanovoys. By 1689, they were driven back by the Manchus. By the Treaty of Nerchinsk (1689) the two empires recognized the Stanovoys and the Argun River as their border. This remained stable until the 1840s.
Following the voyages of Captain James Cook, significant numbers of British, French, and American vessels began entering the Pacific. They were followed by Russians like Grigory Shelikhov and Nikolai Rezanov who were mainly concerned with the new Russian colonies in Alaska. This raised the problem of naval defense of the east coast of Siberia and the possibility of using the Amur River as a supply route to the Pacific.
Muravyov and the Treaty of Aigun (1858)
In 1845, Alexander von Middendorf entered the Amur country and wrote a report. In 1847, reached the mouth of the Amur but could not find a deep-water entrance.
In 1847, Nikolay Muravyov was appointed governor-general of East Siberia. Before leaving for Irkutsk, he arranged for the creation of an Amur Committee to coordinate work in the area. In 1849, he made an overland trip to Okhotsk and then to Petropavlovsk-Kamchatsky. One result of this was the removal of the main naval center from Okhotsk to Petropavlovsk.
In 1848, Gennady Nevelskoy was sent in the Baikal to explore the Pacific coast.
In 1849, Nevelskoy sailed part way up the Amur, and then sailed south through the Tatar Strait, thereby proving that Sakhalin was an island, a fact that was kept a military secret.
In 1850, Nevelskoy founded Nikolayevsk-on-Amur on what was alleged Chinese territory. Karl Nesselrode, the foreign minister, tried to overrule this, but Nicholas I declared "where once the Russian flag is raised, it must not be lowered". Over the next three years, Nevelskoy established other forts on the alleged Chinese territory around the mouth of the Amur.
To establish a military force, Muravyov created a new Cossack host, the Transbaikalian Cossacks, by arming 20,000 mining serfs. In May–June 1854 he and 1,000 men sailed down the Amur to Nikolayevsk. The Manchu governor at Aigun had no choice but to let them pass.
News of the Crimean War reached the far east in July 1854. In September, an Anglo-French naval force was defeated at the Siege of Petropavlovsk. Judging that Petropavlovsk could not be defended, Muravyov ordered Rear Admiral Vasily Zavoyko to move his forces to the Amur area. In May 1855, Charles Elliot's force found Zavoyko at De Kastri Bay (south of Cape Nevelskoy on the Tatar Strait).
Under the cover of fog, Zavoiko withdrew north to the mouth of the Amur, which baffled the British since they thought that Sakhalin was connected to the mainland. In 1855, Muravyov sent a 3,000-man force down the Amur, including settlers. The Chinese declared this to be illegal, but did nothing.
Also in 1855, Russia and Japan signed the Treaty of Shimoda which temporarily resolved their conflict in Sakhalin and the Kuril Islands. The Russian representative was Admiral Putyatin (see below).