Bloody Sunday took place in Russia in 1905. More than 3,000 people marched towards the Winter Palace to Tsar Nicholas II to show him a petition for reform. But he was not at home that day. When he heard about the petition, he became worried (his family had a history of being assassinated) and so the army shot their rifles into the crowd, leaving more than 100 dead and 300 wounded. This event caused the Russian Revolution.