Match the approximate dates on the timeline with the events. German Catherine II becomes czarina after the assassination of her husband, Peter III.

Oleg, a Varangian, unites several cities into Kievan Rus.

Ivan III, known as Ivan the Great, stops tribute payments. He builds Moscow into a large city and declares himself the first czar.

Peter the Great begins to rule.

Mikhail Gorbachev introduces perestroika reforms to overhaul the Soviet Union.

Batu Khan and his skilled Asian horsemen make Russia part of the Mongol Empire.

The October Revolution brings Marxist Vladimir Lenin to power.

French Emperor Napoleon Bonaparte invades Russia with 600,000 troops.

The "Time of Troubles" comes to an end when Michael Romanov becomes czar.