After the February Revolution he organized volunteer units to continue the war, but he became disaffected with the Provisional Government and joined the Left Socialist-Revolutionaries.

In January 1918 he led Red Guard units against the Central Rada of Ukraine and after the Battle of Kruty his forces took Kyiv, where they carried out mass terror against the officers of the imperial army and pro-Ukrainian elements.

However, after he had been named commander of the Eastern Front, fighting the Czechoslovak Legion, he heard of the Left SR uprising against the Bolsheviks in early July and rebelled, sailing down the Volga with a thousand men, hoping to take Simbirsk (Muravyov revolt [ru]).

For seven years he served as a teacher at the Kazan Military School and married the daughter of the commander of the reserve Skopinsky infantry regiment.

At the beginning of World War I, after receiving a number of serious wounds at the front, he was transferred by a tactics teacher to the ensign school in Odessa.

[1] After the defeat of the Kornilov coup, he severed further relations with the Russian Provisional Government and joined the Left Socialist Revolutionaries, who actively criticized Kerensky.

[1] On December 6, 1917, the Council of People's Commissars formed the Southern Front to combat the counter-revolutionaries and Vladimir Antonov-Ovseyenko was appointed to be its commander in chief.

Before the assault itself, on February 4, Muravyov ordered his troops: "to mercilessly destroy all officers, cadets, Haidamakas, monarchists and enemies of the revolution in Kiev".

I burned down Grushevsky’s big house, and for three days it burned with a bright flame ..."Victor A. Savchenko accompanied this statement by Muravyov with the following remark: "Muravyov clearly bragged about his international activities, all the more so since the Czech Republic simply did not exist in February 1918, and Serbia was completely occupied by Austrian troops.

The People's Secretariat of Ukraine, which had moved to Kyiv from Kharkiv, demanded the removal of Muravyov from the city, calling him “the leader of the bandits”.

[2] On February 14, Muravyov was appointed commander of the front, having received the task of opposing the Romanian forces, who sought to seize Bessarabia and Transnistria.

Lenin, on the initiative of Antonov-Ovseenko, offered him the post of commander of the Caucasian Soviet Army, but the local Bolsheviks, headed by the chairman of the Baku Council of People's Commissars Stepan Shaumian, very sharply opposed such a candidate.

[2] The German ambassador Wilhelm von Mirbach, wanting to motivate Muravyov to join the Bolsheviks in the fight against the Czechoslovak Legion, handed him a bribe.

The troops of the front and the Czechoslovak Legion (with which he had to fight before the rebellion) were ordered to move to the Volga and further west to repulse the German invasion.

[1][2] He took the initiative to create the so-called Volga Soviet Republic led by the Left Socialist Revolutionaries Maria Spiridonova, Boris Kamkov and Vladimir Karelin.

[2] In a joint government appeal, Lenin and Trotsky stated that "The former commander-in-chief on the Czech-Slovak front, the left Socialist Revolutionary Muravyov, is declared a traitor and an enemy of the people.

[11] On July 11, Muravyov, with a detachment of a thousand people,[5] arrived at Simbirsk, occupied strategic points of the city and arrested leading Bolsheviks, including the commander of the 1st Army Mikhail Tukhachevsky.

[5] At that time, the local Left SRs were not yet removed from power and held the posts of military, land and food provincial commissars.

[10] By this time, the chairman of the local Bolshevik party committee had managed to secretly place Latvian riflemen, an armored squad and a special detachment of the Cheka around the building.