Cities and the mongol conquest: urban change in Central Asia 1200-1400 ‌ Campbell, K

“…At Merv, the only site to witness a negative impact of the conquest according to the archaeological evidence, the picture is one of depopulation and desertion rather than destruction. …”

الاسلام في داغستان (Al-Islam fi Dagestan) ‌ Kamilov Askhabali, Mudasir Rosder , Abdul Rahman Mahmood

“…The historians agree that the first Islamic conquest to Caucas was in 639M, but the spread of Islam was slow for many reasons. …”