Astemirov, was born in 1976, and claimed descent from a family of Kabardian princes. He was one of a group of young men sent in the early 1990s by the Spiritual Board of Muslims of Kabardino-Balkaria to study theology in Saudi Arabia.
On his return to Nalchik, he and Musa Mukozhev established an Islamic Center that gradually espoused radical Islam, an evolution that brought its members into conflict both with the Spiritual Board and the police. In 2001, Astemirov and Mukozhev were both detained by Russian security forces on suspicion of terrorism, but released after three months.
In 2005, Astemirov gained notoriety as one of the organizers of the abortive multiple attacks by ill-prepared young Muslims on police and security facilities in Nalchik. As the various resistance sub-units began to expand their use of the Internet as a propaganda tool, Astemirov emerged as its first prominent Islamic ideologue, posting numerous homilies on the subject of jihad.
Astemirov is said to have played a key role in persuading then-Chechen Republic-Ichkeria (ChRI) President and resistance commander Dokka Umarov in late 2007 to jettison the cause of Chechen independence in favor of creating an independent Muslim state comprising the entire North Caucasus.
In 2008, Umarov named him head of the Shari'a court of the "North Caucasus Emirate," the third-most-senior position (after Umarov and his deputy Amir Magas*) in the insurgency hierarchy. In that legal capacity, Astemirov signed a death sentence in August 2009 on ChRI Prime Minister Akhmed Zakayev on the grounds that Zakayev had allegedly renounced Islam in favor of "democratic religion."
Astemirov's death leaves the insurgency without an experienced and charismatic military leader in the Northwest Caucasus. The statement confirming his death claimed that "the Circassian peoples have not had a military commander who enjoyed such respect and authority" since the Caucasus wars of the 19th century.
But with the possible exception of the high-profile assassination by insurgents in January 2008 of a senior Kabardino-Balkaria Interior Ministry official, that republic and neighboring Karachayevo-Cherkessia have in recent years been an oasis of relative calm and stability compared with Ingushetia and Daghestan, where insurgent attacks on police and security forces occur almost daily.
Astemirov's death is therefore unlikely to have little immediate impact on the incidence of fighting.
It is, however, nonetheless a serious blow for the insurgency, just weeks after the killing in Ingushetia of a second prominent Islamist ideologue, Said Buryatsky, and when the rumored death of Umarov himself in a shoot-out on March 10 has still not been confirmed.
* Correction: The original version of this article incorrectly identified Umarov's deputy as Supyan Abdullayev, instead of Amir Magas.