The document discusses Russia under the Tsars from the 14th to late 18th centuries. It covers Russia's expansion across central Asia and Siberia through recruited Cossacks. Peter the Great modernized Russia by westernizing the bureaucracy, military, and culture. He established St. Petersburg and forced nobles to adopt western dress. Catherine the Great consolidated power and continued westernizing reforms while expanding further into Crimea and Siberia. Serfdom increased over this time period, trapping 95% of the rural population with few rights and social unrest grew by the late 18th century.