Mass demonstrations against food shortages in Petrograd (March 8-16, 1917) evolved into a general revolt against Tsar Nicholas II. The military garrison joined the uprising, causing the Tsarist government to collapse. Nicholas II abdicated on March 15, ending the 304-year Romanov dynasty. Power transferred to the Provisional Government, initially led by Prince Lvov and later by Alexander Kerensky. The revolution transformed Russia from an autocracy to a republic and preceded the Bolshevik Revolution in October 1917.