Russia is actually a much more diverse country than many realize, with several ethnic groups and states making up the larger Russian Federation. Chechnya is one of those states, home to an ethnic group known as Chechens. Following the dissolution of the Soviet Union in 1991, Chechnya attempted to become its own independent territory as many of the former Soviet states did. A similar struggle took place in neighboring Dagestan, which, much like Chechnya, is a Muslim majority state within Russia where the suspects are believed to have lived for a time before emigrating to the United States. The Russian federal government launched several all-out wars to keep Chechnya within the country. The last open conflict ended in 1999, with Russian President Vladamir Putin accused of using excessive force against civilians.
Moscow’s victory in the North Caucasus has never been fully cemented, due to an on and off struggle between the separatists in the states and the central government. Various social media accounts discovered possibly belonging to the two suspects indicate that both share a heavy interest in Chechen issues.
Several Chechen separatists groups still exist and have carried out many heinous attacks over the years. The most notorious of these was in the Russian city Beslan, when a Chechen group took an elementary school hostage in 2004. More than 300 hostages were killed during the incident, including 186 children. Chechen separatists were also behind a hostage taking at a Moscow theater, which ended with the Russian government accidentally killing 130 of those inside the building. Chechens have also been identified or suspected as jihadi fighters in conflicts around the world, including in Syria, while continuing to wage an insurgency against Moscow for the establishment of an Islamic state in Chechnya.
Unfortunately, this does not tell us very much at the moment. An ethnicity does not indicate any sort of defined motive or ties to any possible group or groups and law enforcement has yet to provide any confirmation of the current reporting. Chechen groups also have traditionally focused their ire on Russia rather than targeting the United States. Finally, given their lengthy residence it is difficult to discern what — if any — ties or sympathies the two brothers have to Chechen terrorist groups. The older of the brothers — Tamerlan Tsarnaev — has been in the United States since as early as 1992 as a refugee and in 2002 hoped to box for the United States at the Salt Lake City Olympics.