Ukraine's fledgling government is warning that Russia's actions in Crimea—the strategic peninsula that juts into the Black Sea and is home to Russia's Black Sea Fleet—is part of a historical tactic to gain control over former Soviet territory. "They are provoking us into an armed conflict," said interim president Oleksandr Turchynov. "Based on our intelligence, they're working on scenarios analogous to Abkhazia, in which they provoke conflict, and then they start to annex territory."

The "annexation" that the newly minted Ukrainian leader is referring to is that of the mountainous region of Abkhazia on the eastern coast of the Black Sea, just three miles south of Sochi. The region had been long simmering: A war in 1992-93 led to some 8,000 deaths and 240,000 displaced people, according to the International Crisis Group. South Ossetia had also been a part of the former Soviet republic of Georgia, but after a conflict in the early 1990s, its status remained nebulous until it became the second Georgian territory to be effectively lost to Moscow. After its defeat to the Russians in a five-day war in 2008, Georgia declared the area "Russian-occupied territory."

Now it could be Ukraine's turn. Russians officials told the UN Security Council that ousted Ukrainian president Viktor Yanukovych had written to Vladimir Putin that "Ukraine is on the brink of civil war" and needs Russian armed forces to keep the peace. What is unfolding in Crimea today, says Steven Pifer, a Brookings Institution expert and former U.S. ambassador to Ukraine "is a military occupation. The Russians may not have decided what they will do next."

What many fear could happen next is further turmoil in geographic regions historically loyal to Moscow—that Crimea will be the spark for violence in Ukraine's eastern and historically Russian-leaning regions east of the Dnieper River. (See "How History, Geography Help Explain Ukraine's Political Crisis.")

View Images Georgian families and soldiers await evacuation as Georgian troops fight separatist Abkhazians. Photograph by AP

Post-Soviet Frozen Conflicts

Or, if the events in Crimea are contained, the peninsula could join South Ossetia and Abhkazia and Nagorno Karabakh to become yet another post-Soviet "frozen conflict" - areas where armed conflict has come to end but the political status of a region remains unresolved. (See "The Rebirth of Armenia.") After flexing its military might, Russia could gain effective control of a territory once belonging to a neighboring and sovereign state, and would manage to keep it indefinitely.

During the Soviet period, satellite states beginning to show signs of unrest and independence also met with swift Russian-led interventions, often—as in today's Ukraine—under the pretext of requests from embattled local allies: the Hungarian revolution of 1956, the Prague Spring and subsequent invasion along with Warsaw Pact troops of Czechoslovakia in 1968, and the invasion of Afghanistan in 1979. Chechnya, the Russian republic that tried to wrest free of the Kremlin, also faced a formidable response from Moscow. It found itself mired in years of warfare resulting in an estimated 160,000 deaths and—after Vladimir Putin became president of Russia—was brought firmly back under Russian control.

Yet some regions suddenly freed from Moscow's reach didn't want the post-Soviet liberty. Trans-Dniester, a slip of land between the Dniester River and the eastern Moldovan border with Ukraine, remains unrecognized by any UN member state. But it is considered to be under the effective authority and influence of Russia after it broke free from Moldova in 1992 with the help of the Russian Army, conveniently stationed near its capital, Tiraspol.

View Images A Chechen man shows his support for Chechen separatist fighters seated atop an armored personnel carrier. Photograph by Misha Japaridze, AP

History and Geography Contribute to Crimean Conflict

Russian forces are also conveniently located in Crimea, where a largely Russian populace (59 percent; Crimea was a part of Russia until 1954)—has so far welcomed the Russian forces. Twelve percent of Crimea's population, however, is made up Crimean Tartars, who once ruled the peninsula. "The defeat of the Tartar Khanate, with its seat in Crimea, was a key moment in the expansion of the Russian Empire," says Keith Darden, associate professor at American University researching the roots of nationalist loyalties in the former Soviet Union and other countries. Formally annexed by Russia in 1783, "it led the settlement of a lot of Russians in the area." Those Crimean Tartars—a Muslim population that was deported by Joseph Stalin during World War II, but began to return in greater numbers in the 1990s—lean more heavily in support of the pro-Western and anti-Yanukovych protestors in Kiev.

The Crimean War of 1853-56, when Russia fought the Ottoman Empire and its European allies over control of Crimea, may have been the last time so many global powers had their eyes on the tiny peninsula, but the conditions are entirely different now. "The Crimean War was about the great power diplomacy of the 19th century—it had nothing to do with the loyalties of the population, but everything in Ukraine now does," says Darden. "This time the great powers are constrained by what the people want."

Geography may also serve as a constraint. Maria Lipman, an analyst with the Carnegie Moscow Center, says that "geographically speaking" the peninsula has some interesting challenges. For example, in the north "it has a narrow strip of land that connects it to Ukraine. The peninsula itself is very dry, with almost no source of fresh water," and thus relies on mainland Ukraine for water. "Crimea cannot simply be severed from Ukraine." To its east, however, is the Strait of Kerch; the Russian prime minister has called for construction of a bridge connecting Crimea to the mainland.