Askeran Rayon was one of the five rayons of the former Nagorno-Karabakh Autonomous Oblast (NKAO) of the Azerbaijan Soviet Socialist Republic (AzSSR). Its capital was Askeran (town)
Until 1978 it was called Stepanakert Rayon and its capital was Stepanakert.
References
Askeran District (NKAO) Wikipedia(Text) CC BY-SA