He attended the Bila Tserkva Gymnasium, supporting himself through teaching and became an active social democrat. Moisei studied law at the University of Kiev.
During his studies he joined the Russian Social Democratic Labour Party and organized an underground network for importing and distributing political literature. In 1897 he was arrested and exiled for running an illegal mimeograph press Becoming involved in the revolutionary movement, he participated in the revolutionary Jewish Bund.
In 1903, he became a Menshevik.
His activities in St. Petersburg during the 1905 revolution earned him a second term of exile. Along with Alexander Parvus he was active in dispatching revolutionary agents to infiltrate the Tsarist security apparatus.
In 1914 he emigrated to France and contributed to the Party newspaper Our Word. A few months before the October Revolution of 1917, he joined the Bolsheviks and was elected to their Central Committee in July 1917.
Uritsky played a leading part in the Bolsheviks" armed take-over in October and later was made head of the Petrograd Extraordinary Commission Against Counterrevolution, Sabotage and Speculation.
Because Uritsky was against the Treaty of Brest-Litovsk, he resigned his post in 1918, like Bukharin, Bubnov, Piatakov, Dzherzhinsky and Smirnov. On March 4, 1918, the Petrograd committee published the first number of the journal Kommunist, the public organ of the "left communist" opposition, as directed by Radek and Uritsky. The Extraordinary Seventh Congress of the Bolshevik party, which was held between March 6 and 8, 1918, rejected the Theses on the Present Situation that was submitted as a resolution by the "Left Communists".
The "Left Communists" Lomov and Uritsky, who were elected to the Central Committee, stated at the Congress that they would not work in the Central Committee, and did not begin work there for several months in spite of insistent demands from the Central Committee.
On May 25, 1918, with the Revolt of the Czechoslovak Legion, the Russian Civil War began and Uritsky resumed his position on the Central Committee. Leonid Kannegisser, a young military cadet, assassinated Uritsky on August 17, 1918 in retaliation for the execution of his friend and other officers.
Following this event, along with the assassination attempt on Lenin by Fanya Kaplan on August 30, the Bolsheviks began a wave of persecution known as the Red Terror. Palace Square in Petrograd was known as Uritsky Square from 1918 to 1944.
Bolsheviks, Communist Party of the Soviet Union.
Back in Russia in 1917 Uritsky became a member of the Mezhraiontsy group.