Russian Revolution: A series of revolutions in Russia between 1905 and 1917 that ultimately resulted in the overthrow of Tsar Nicholas II.
Marxism-Leninism:A political ideology combining Marxist principles with Leninist strategies for achieving socialist revolution.
October Manifesto: Issued by Tsar Nicholas II after the 1905 revolution, it promised civil liberties and created an elected legislative body known as the Duma.