What were the causes of 1905 Russian revolution? Who led it? And what was the result?

The immediate causes of the 1905 revolution were failed state-level leadership and policy, inflation poverty, hunger, Russo-Japanese War, the rise of reformer and revolutionary groups, and Bloody Sunday. The industrial revolution came to Russia with a lot of changes such as social and political. The population was increasing in urban cities such as St. Petersburg and Moscow. Such an increase in the population was becoming a problem for the country due to the limited food supply because of the economic crisis and mismanagement and costly wars. Due to the shortage of food supply and present conditions, the people marched towards the Winter Palace of Nicholas II on Jan 22, 1905. Luckily, he was not there and he ordered not to shoot at the crowd but due to some miscommunication his orders were ignored and the troops fired the crowd. This event is the history is known as the Bloody Sunday Massacre. This even fueled the Russian revolution of 1905. 
Consequences-It included worker strikes, peasant unrest, and military mutinies. It led to constitutional reform (namely the "October Manifesto"), including the establishment of the State Duma, the multi-party system, and the Russian Constitution of 1906.
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