6 3 2 – 6 6 0 ) ▁extended ▁domin ion ▁of ▁Great ▁Bulgar ian ▁On og uria ▁into ▁P ann onia ▁placing ▁Pse udo - Av ars ▁under ▁K uber ▁in ▁S irm ium . ▁Bat bay an ▁ruled ▁two ▁years ▁before ▁being ▁challeng ed ▁and ▁sent ▁to ▁It il ▁by ▁his ▁brother ▁Kot rag ▁who ▁ens ured ▁Kh azar ▁rule ▁over ▁a ▁loose ▁conf eder ation ▁of ▁trib al ▁city - states ▁from ▁K iev ▁in ▁the ▁West ▁to ▁Bol g har ▁in ▁the ▁N ortheast ▁and ▁the ▁C asp ian ▁G ates ▁in ▁the ▁S out heast . ▁ ▁Kh azar ▁r ul ers ▁ ▁Kh azar ▁Kh agan ate ▁controlled ▁much ▁of ▁what ▁is ▁today ▁southern ▁and ▁eastern ▁Ukraine ▁until ▁the ▁ 1 0 th ▁century . ▁ ▁Bul an ▁Sab riel ▁( fl . ▁c . ▁ 7 4 0 ) ▁Ob ad iah ▁( c . ▁ 7 8 6 – 8 0 9 ) ▁He zek iah ▁ben ▁Ob ad iah ▁Man asse h ▁I ▁ben ▁He zek iah ▁Han uk k ah ▁ben ▁Ob ad iah ▁Isaac ▁ben ▁Han uk k ah ▁Z eb ul un ▁ben ▁Isaac ▁Man asse h ▁II ▁ben ▁Z eb ul un ▁N isi ▁ben ▁Man asse h ▁A aron ▁I ▁ben ▁N isi ▁( fl . ▁c . ▁ 9 0 0 ) ▁Men ah em ▁ben ▁A aron ▁( fl . ▁c . ▁ 9 1 0 ) ▁Benjamin ▁ben ▁Men ah em ▁( fl . ▁c .