Answer:
The Russian Revolution where the Bolshevik party seized control of Russian government. The attacks and uprisings were mostly focused on St. Petersburg where the royal family lived. All of the royal family, including the czar was killed by a firing squad following the revolt.
The reason for the revolution was largely civil unrest. A great number of people were not happy with the way Czar Nicolas II handled his troops and rations. Also, there was a great deal of wealth inequality, where most people were poor while some few had most of the wealth. A famous theorist, Carl Marx, inspired the Bolshevik parties ideals- also known as communism.
Following the revolution, the Soviet Union, or USSR was established, and it wasn't until the 1980's that it collapsed.