Deadly street battles between protesters and police in the Ukrainian capital have raised fears that the former Soviet nation, whose loyalties are split between Russia and the West, is in an uncontrollable spiral toward civil war.
Deep roots of history: Moscow sees Ukraine as the birthplace of Russian statehood and Russian Orthodox Christianity. Most of modern-day Ukraine came under the control of the Russian czars in the 1700s after being part of the Polish-Lithuanian Commonwealth. Ukraine remained under Moscow's control until the 1991 collapse of the Soviet Union.
Ukraine's economy: The Ukrainian republic was the most important economic component of the former Soviet Union. Its diversified heavy industry supplied the equipment and raw materials to industrial and mining sites in other regions of the former USSR. Ukraine depends on imports to meet about three-fourths of its annual oil and natural gas requirements and 100% of its nuclear fuel needs. After a two-week dispute that saw gas supplies cutoff to Europe, Ukraine agreed to 10-year gas supply and transit contracts with Russia in January 2009.
East vs. west: About one-third of Ukraine's 46 million citizens, including President Viktor Yanukovych, speak Russian as their native language. The other two-thirds speak Ukrainian and identify more closely with western Europe. Yanukovych is widely despised in Ukraine's west, but has strong support in his native Russia-speaking east and south, where the majority of the population depends on trade with Russia and supports close ties with Moscow. The sharp divide between east and west has fueled fears of a messy breakup of the country.
Russia's role: Russian President Vladimir Putin sees close economic and political ties with Ukraine as essential for the success of his project to build an alliance of ex-Soviet neighbors. Russia has done its best to derail Ukraine's pact with the EU with a mixture of trade sanctions and promises. After Yanukovych spiked the deal, Moscow offered a $15 billion bailout to help Ukraine avoid an imminent default, but so far has only provided $3 billion, freezing further disbursements pending the outcome of the ongoing strife.
Associated Press, CIA World Factbook