16 (28) May, 1858 in Aigun, Russia and China "... by mutual agreement, for the eternal mutual friendship between the two countries and for the benefit of their citizens ..." concluded the Treaty of Aigun. From the Russian side the agreement was signed by the Governor-General of Eastern Siberia, Lieutenant-General, Earl N. N. Muravyov-Amursky, from the side of China - Aigun headman, Adjutant General, court dignitary, Amur Commander in Chief, prince Yishan. The treaty was prepared by a lengthy process of development of the Amur and served the cause of strengthening Russia's positions on the Pacific coast.
In 1851-1853, the expedition of Captain Nevel was sent to the Sea of Okhotsk. It proved navigability of the Amur and explored the Sakhalin, the Sea of Okhotsk and the Tatar Strait. At the mouth of the Amur were founded the first Russian settlements and military posts. During the Crimean War, Russia, seeking to strengthen its position on the Pacific coast and on the approaches to North China, arranged the navigation of Russian ships in the Amur and established military posts along the Manchurian border. Later, taking advantage of the weakening of China as a result of defeat in the war of 1856-1858 with Britain and France, and the Taiping rebellion, Russia demanded that China recognized the entire Maritime region as the Russian possession. After six-day talks, in Aygun was signed the treaty containing three clauses.
The Treaty of Aigun legally established as the Russian possession the left bank of the Amur River from the Argun River to the mouth; the right bank of the Amur River up to the Ussuri River belonged to China. The region between the Ussuri and the sea "... until the establishment there the boundary between the two countries ..." was declared the common possession of Russia and China. Navigation in the Amur, Ussuri and Sungari was allowed only for Russian and Chinese vessels.
Russian and Chinese people living along these rivers were authorized to mutual trade. The parties mutually pledged to protect "the trading people..." of the two states.
The Treaty of Aigun was approved by the decree of the emperor (the emperor of China) 2 (14) June 1858 and ratified by the Russian Empire 8 (20) June 1858.
The treaty legally authorized Russia to possess the territory which was assigned to it by the Treaty of Nerchinsk of 1689. The final border between Russia and China in the Far East, was defined by the Treaty of Beijing in 1860, which confirmed the Treaties of Aigun and Tianjin as well as set the border along the Ussuri River.
Lit.: Айгунский договор между Россией и Китаем о границах и взаимной торговле. Айхунь [Айгун], 16/28 мая 1858 г. // Сборник договоров России с другими государствами. 1856-1917. М., 1952; То же [Электронный ресурс]. URL: http://www.hist.msu.ru/ER/Etext/FOREIGN/aigun.htm; Гримм Э. Д. Сборник договоров и других документов по истории международных отношений на Дальнем Востоке (1842-1925). М., 1927; Романов Д. Присоединение Амура к России. Период III. Возвращение Амура (1847-1858) // Русское слово. 1859. Июль-август; Шумахер П. К истории приобретения Амура. Сношения с Китаем с 1848 по 1860 г. // Русский архив. 1878. Кн. 3. № 11.
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