In 1840, Muravyov was assigned to command one of the sections of the Black Sea coast defense lines, during which time he participated in the suppression of the Ubykh people.
He transferred to the Ministry of Internal Affairs and was appointed as an acting military and civil governor of Tula province in 1846.
Eager in his willingness to improve the province's state of affairs, he proposed to establish the governorate agricultural society.
Contrary to the views of Karl Nesselrode, the Russian Foreign Minister, Muravyov was personally instructed by Tsar Nicholas I to press for an advantage against China.
Muravyov insisted on conducting an aggressive policy with China despite strong resistance from St Petersburg officials, who feared a breakdown in relations between the two countries.
Nevertheless, because the lower reaches of the Amur River were, in fact, being claimed by the Russians, several expeditions organized by Gennady Nevelskoy had been approved by the government.
Due to the Crimean War, a portion of the fleet was then sent to Kamchatka's Avacha Bay, where a series of artillery batteries was established to defend the peninsula.
The Chinese were initially against setting any kinds of boundaries along the Amur River, preferring the status quo of keeping the adjacent territories under joint control of Russia and China.
According to an article by the Russian novelist Vladimir Barayev, the signing of the treaty was celebrated by grandiose illumination in Peking and festivities in major Siberian cities.
As a governor general of Eastern Siberia, Muravyov-Amursky made numerous attempts to settle the shores of the Amur River.
As the main objection of the St. Petersburg officials against taking over the left bank of the Amur was lack of people to defend the new territories, Muravyov-Amursky successfully petitioned to free Nerchinsk peasants from mandatory works in the ore mines.
In 1868, he moved to Paris, France, where he lived until his death in 1881, visiting Russia only occasionally to participate in the State Council meetings.