Peter the Great
Peter the Great was probably the most discussed, most controversial and most extraordinary Russian Tsar. Determined to bring Russia back on her feet and to make her a modern European state, Peter the Great wouldn't stop at nothing, thus making Russia's way to progress rather painful.
As a child he had seen relatives murdered in Kremlin during the Streltsy rebellion (strelets - member of privileged military corps in the 17th century Russia). This may have affected his character developing his predisposition to fits of rage and a pathological distrust for Moscow. 16 years later Peter got the chance for revenge on the Streltsys, when he executed over a thousand of them after another rebellion. This was a perfect demonstration of how he used to deal with his enemies.
Hatred for patriarchal Moscow and desire to change stagnant way of living in Russia forced Peter the Great to carry out many crucial reforms. In order to get familiar with modern European technologies in shipbuilding and other fields, he became the first tsar ever to go abroad with the aim of studying. After this educational trip Peter got reforms going: he built Russian navy, reformed the army, restructured administrative system, supported the development of Russian industry and trade. He was also a very successful commander, defeating the Swedes, who had been a threat to Russia for more than a century, and the Turks, giving Russia free access to the Black and Caspian Sea. All this allowed to say that Peter the Great "hacked a window to Europe" for Russia.
Being an admirer of Western life, Peter the Great insisted on Western style clothing for his courtiers, literally shaved boyars' beards, which reminded him of so much hated old Russia. His reforms split Russian society into Slavophiles and Westerners; this division lasted for centuries. Peter's final step in fighting the spirit of old Russia was the removal of the capital from Moscow to recently built pompous St.Petersburg, a city standing on the swamps and bones of dead builders. For the next 200 years Moscow existed in St.Petersburg's shadow being Russia's second city.