and served to encourage revolutionaries. A parliament—the State Duma—was established in 1906 after the Russian Revolution of 1905, but Emperor Nicholas II resisted attempts to move from absolute to a constitutional monarchy. Social unrest continued and was aggravated during World War I by military defeat and food shortages in major cities. A spontaneous popular demonstration in Petrograd on 8 March 1917, demanding peace and bread, culminated in the February Revolution and the toppling of Nicholas II and the imperial government. The tsarist autocracy was replaced by the Russian Provisional Government, which intended to conduct elections to the Russian Constituent Assembly and to continue fighting on the side of the Entente in World War I. At the same time, workers' councils, known in Russian as ‘Soviets’, sprang up across the country, and the most influential of them, the Petrograd Soviet of Workers' and Soldiers' Deputies, shared power with the Provisional Government. The Bolsheviks, led by Vladimir Lenin, pushed for socialist revolution in the Soviets and on the streets, adopting the slogan of “All Power to the Soviets” and urging the overthrow of the Provisional Government. On 7 November 1917, Bolshevik Red Guards stormed the Winter Palace in Petrograd, arresting the Provisional Government leaders and Lenin declared that all power was now transferred to the Soviets. This event would later be officially known in Soviet bibliographies as the "Great October Socialist Revolution". The bloody Red Terror was initiated to shut down all opposition, both perceived and real. In December, the Bolsheviks signed an armistice with the Central Powers, though by February 1918, fighting had resumed. In March, the Soviets ended involvement in the war and signed the Treaty of Brest-Litovsk. A long and bloody Civil War ensued between the Reds and the Whites, starting in 1917 and ending in 1923 with the Reds' victory. It included foreign intervention, the execution of the former Emperor and his family, and the famine of 1921, which killed about five million people. In March 1921, during a related war with Poland, the Peace of Riga was signed, splitting disputed territories in Belarus and Ukraine between the Republic of Poland and Soviet Russia. Soviet Russia sought to re-conquer all newly independent nations of the former Empire, although their success was limited. Estonia, Finland, Latvia, and Lithuania all repelled Soviet invasions, while Ukraine, Belarus (as a result of the Polish–Soviet War), Armenia, Azerbaijan and Georgia were occupied by