The two brothers suspected in the Boston Marathon bombings—one of whom is dead, the other provoking a massive manhunt across Boston on Friday—are Chechens who were raised in Dagestan and Kyrgyzstan before immigrating to the United States, according to news reports.
While nothing has yet been found linking brothers Tamerlan Tsarnaev, 26, who was killed by authorities, and 19-year-old Dzhokhar Tsarnaev to Chechen terrorist organizations, their ethnicity has once again directed attention to Russia's Caucasus region. (Read "Chechnya: How did it come to this?" in National Geographic magazine.)
The area occupies Russia's underbelly, situated between the Caspian and Black Seas, and has been a cauldron of ethnic and nationalist discontent for centuries.
First subdued by the tsars in the 19th century, the Caucasus are a patchwork of peoples, languages, and cultures that have always stood distinct from their Russian rulers.
From Georgians in the west to Azeris in the south to Chechens, Dagestanis, and Circassians in the north, the region is riven with boundaries of uncertain provenance.
As the early-19th century French diplomat Jacques-François Gamba wrote of his travels through the territories, "I could never quite determine if these limits were established by politics or by invasions, or if they naturally separated two peoples who have nothing in common in terms of language, traits and character."
Among these many peoples, Chechens and Dagestanis (an umbrella term for Avars, Dargins, Kumyks, and Lezgins, and other ethnicities) acquired a reputation for rebelliousness and violence. During the Russian campaign to subdue the Caucasus and secure the route to Transcaucasia from 1817-1863, Chechen and Dagestan fighters under Imam Shamil waged a decades-long guerrilla campaign against the Russian colonizers.
The brutal war decimated the Chechen population in the Caucasus, reducing its numbers from an estimated one million in the 1840s to 140,000 in 1861.
Over the course of the next century, Islamic Chechens and Dagestanis continued to be viewed with a wary eye by Moscow. That suspicion reached its apogee during World War II, when "Chechens were deported from Chechnya on Stalin's orders. . . and were forced to settle in Central Asia," so concerned Stalin was of their separatist tendencies, said William Pomeranz, a Russian and Caucasus expert at the Woodrow Wilson Center, in an interview.
An estimated one quarter to one half of the population died in transit to Siberia and Kazakhstan. Though "rehabilitated" in 1956 and allowed to return to their lands in 1957, Chechens and Dagestanis remained outsiders in Soviet society.
The breakup of the Soviet Union in 1991 rekindled a sense of strong national identity in Chechnya, whose population is today about 95-percent Muslim, according to official Russian statistics.
Chechnya's defiant declaration of sovereignty brought on a crackdown from Moscow, sparking the first of two full-fledged separatist wars fought over the decade. The clash lasted from 1994 to 1996, causing a massive loss of civilian life and reducing the republic's capital city of Grozny to ruins.
"The Chechen were essentially ungovernable in the early 1990s," said Pomeranz. "Chechnya's story of the early 1990s is that of separatism and violence."
A fragile peace treaty signed with Russia in 1996 failed to bring stability and Chechnya plunged into political disorder.
A second wave of Russian military action lasted from 1999 to 2000—the years when the Tsarnaev family lived in the neighboring state of Dagestan. Dzhokhar, the younger brother, attended primary school in the city of Makhachkala, according to his page on the Russian social networking website VKontakte.
Moscow has since gradually re-established its authority over Grozny and the rest of Chechnya, bringing in both the security forces to maintain control and the funds necessary for post-war reconstruction.
Tensions have continued to simmer under the surface, however, boiling over as sporadic acts of large-scale violence, such as the 2004 hostage crisis at a school in Beslan, North Ossetia, that claimed 330 lives, many of them children.
In Moscow, militants from Chechnya and the North Caucasus region were behind the bombing of the city metro in 2010, in which 40 people died, and the 2002 hostage-taking crisis in a Moscow theater that resulted in 129 hostage deaths.
In Russia, the memory of these acts breeds mistrust between ethnic Chechens and the dominant Russian majority. "Russia has enormous ethnic diversity, but there remain ethnic populations that are very much outsiders—and Chechnya fits that role too," said Lincoln Mitchell, professor at Columbia University's Harriman Institute for Russian and Eurasian Studies.
It remains unclear how much time Dzhokhar and Tamerlan Tsarnaev spent in Chechnya as children before their family immigrated to the United States in 2002 and 2003, or how strong their bond was with the North Caucasus.
The brothers appear to have grown up in Kyrgyzstan, not Chechnya, although the family temporarily lived in Dagestan before their move, and the brothers' father continues to live there, according to the Associated Press.