With a population of 2,910,249, Dagestan is very ethnically diverse and Russia's most heterogeneous republic, with none of its several dozen ethnicities and subgroups forming a majority. Largest among these ethnicities are the Avar, Dargin, Kumyk, Lezgian, Laks, Azerbaijani, Tabasaran, and Chechen. Ethnic Russians comprise about 3.6% of Dagestan's total population. Russian is the primary official language and the lingua franca among the ethnicities.
Dagestan has been a scene of Islamic insurgency, occasional outbreaks of separatism, and ethnic tension since the 1990s. According to International Crisis Group, the militant Islamist organization Shariat Jamaat is responsible for much of the violence. Much of the tension is rooted in an internal Islamic conflict between traditional Sufi groups advocating secular government and more recently introduced Salafist teachers preaching the implementation of a certain form of Sharia in Dagestan.
The name Dagestan referred to Dagestan Oblast during 1860 to 1920, corresponding to the southeastern part of the present-day Republic. The current borders were created with the establishment of the Dagestan Autonomous Soviet Socialist Republic in 1921, by the inclusion of the eastern part of Terek Oblast, which is not "mountainous" at all but includes the Terek littoral at the southern end of the Caspian Depression.