Who is Vladimir Ilyich Ulyanov from Nicholas and Alexandra and what is their importance?

Vladimir Ilyich Ulyanov went by the name of Lenin and was one of the leaders of the Revolution. He also grew up in Simbirsk with Kerensky. Vladimir was born in 1870 to a father who was the son of a freed serf. His father was a mathematics teacher who rose through the ranks and became an administrator. His older brother Alexander was arrested in 1887 for his involvement in a plot to kill the Tsar and was hanged. Vladimir was expelled from the University of Kazan for taking part in a demonstration and his mother bought a farm and made him the manager, as she tried to save him from the same fate his brother had suffered.