Abu Omar al Shishani, whose real name is Tarkhan Batirashvili, appears with other Russian-speaking Islamic State fighters in an Islamic State video, from which this image was captured. Ethnic Chechens, who have fought two wars in a failed effort to achieve independence from Russia, are among the largest groups of Islamic State foreign fighters. Screenshot from ISIS Video

U.S. Training Helped Mold Top ISIS Commander

In Syria, he’s known as Abu Omar al Shishani, commander in several major victories.