Russian politican and right-wing extremist who in 1905 was one of the founders of the Union of the Russian People (URP), a reactionary group active before the Russian Revolution and noted for its violent attacks against Jews and leftists.

A landowner and onetime government official, Purishkevich also served as a deputy to the second through fourth state Dumas (parliaments), in which he made anti-Semitic speeches. Purishkevich quickly established himself as a leader of the extreme reactionaries in the Duma, claiming at one point, “To the right of me there is only the wall.” He combined unswerving loyalty to the monarchy with a firm commitment to ethnic Russian domination of the Empire's minority nationalities, and he had an unyielding hatred for liberals, socialists, and Jews.

In 1908, after a personality clash with other URP leaders, Purishkevich formed a splinter group known as the Union of the Archangel Michael. A vigourous supporter of the Russian war effort during World War I, Purishkevich was one of the conspirators in the murder of Grigory Rasputin in December 1916.

After the abdication of the Tsar in February 1917, Purishkevich planned the escape of the imperial family from the provisional government. During the revolution in November (October, O.S.) he led a counterrevolutionary conspiracy in Petrograd. Imprisoned by a Soviet court, he was amnestied in May 1918 and moved to southern Russia, where he worked with White forces and published an anti-Soviet newspaper. He died of typhus.