Main Events and Effects    
(a)February Revolution   
(i) 22 February Lockout of a factory was done on the right bank of the Neva river in Petrograd. 
(ii) 23 February Sympathy strike was done by workers in 50 factories. Demonstrating workers reached the centre of the city, surrounding the government buildings. Curfew was imposed  and the demonstrators dispersed. 
(iii) 24 and 25 February Demonstrations done again by workers. Cavalry and police were called out to control them. 
(iv) 25 February  Government suspended the Duma (Russian Parliament). 
(v) 26 February Demonstrators returned in force to the streets of the left bank. 
(vi) 27 February Workers ransacked the Police Headquarters. Streets were thronged with people shouting slogans demanding bread, better wages, less hours of work and democracy. Cavalry was called out once again, but they refused to fire on the demonstrators. By evening, soldiers and striking workers formed a 'Soviet' (council) which was called the Petrograd Soviet. 
(vii) 28 February A delegation met the Tsar. Army commanders advised him to abdicate. 
(viii) 2 March Tsar abdicates. Duma leaders and others form a provisional government. Who was Involved; the Leaders and its Impact Both men and women workers were involved. There were no particular leaders. The effect was that it brought down the autocratic monarchy.  
(b) October Revolution 
(i) 16 October Lenin persuades the Petrograd Soviet and Bolshevik Party to agree to a socialist seizure of power. Military Revolutionary Committee to manage this operation was formed.  
(ii) 24 October   Uprising starts, but government troops seize buildings of two Bolshevik newspapers. The Winter Palace and other buildings were also protected by troops. The Military Revolutionary Committee seized the government offices and arrested the ministers. The ship Aurora shelled the winter palace. By nightfall, the city was under the Committee's control and the remaining ministers had surrendered. Who was Involved, the Leaders and Its Impact Bolsheviks were the main people involved. Vladimir Lenin and Leon Trotskii were the main leaders. The effect was that it brought the Bolsheviks to power to form a communist government for the first time in the world.