Russia's incursion into the Crimean region of Ukraine has once again thrust Vladimir Putin to the forefront of the world stage.
Just who is the man at the center of perhaps the most dangerous crisis to hit Europe since the end of the Cold War?
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Putin was born in Leningrad, which is now known as St. Petersburg, on Oct. 7, 1952. Putin grew up living in a communal apartment. His father, also named Vladimir, worked as a factory foreman.
Putin received a degree from the law department at Leningrad State University in 1975, and that same year, he joined the KGB, beginning a long career as a Soviet intelligence officer.
In 1983, Putin married wife Lyudmilla, and the couple would have two daughters. Last year, the Putins announced that their marriage was ending.
During the latter half of the 1980s, Putin was stationed in East Germany.
Putin took a job at Leningrad State University in 1990. Not long after, he began working as an aide to to Anatoly Sobchak, who would become mayor of St. Petersburg. Putin would hold posts in St. Petersburg's government in the early-to-mid 1990s.
In 1996, Putin moved to Moscow and began his rapid ascent to the top levels of Russian leadership.
He held posts in President Boris Yeltsin's government, and in 1998, became head of the Federal Security Service, the agency that was essentially the successor to the KGB.
The next year, in August 1999, Yeltsin tapped Putin as acting prime minister. Just a few months later, Yeltsin resigned, handing over the reins of power to the then-47-year-old Putin, who became acting president. Putin would win the presidency in his own right in a March 2000 election and won re-election four years later.
Putin would leave the presidency in 2008 due to term limits, but he was installed as prime minister by his successor, Dmitry Medvedev, leading many to believe Putin still retained the ultimate power in Russia. In 2012, there would be no doubt who was in charge, as Putin once again was elected president.
Putin's relationship with American leaders has been complicated, to say the least. In 2001, President George W. Bush famously told reporters he "was able to get a sense of his soul," calling him "straightforward" and "trustworthy." Years later, while seeking the 2008 GOP presidential nomination, Arizona Sen. John McCain said: "I looked into Mr. Putin's eyes and I saw three things: a K, and a G and a B." In a 90-minute call with Putin on Saturday, President Obama had what was reported as a tense exchange with the Russian leader over the Ukrainian crisis.
Beyond politics, what are the Russian president's hobbies? Perhaps not surprisingly, Putin holds a black belt in judo.