▁administration ▁by ▁Imperial ▁Roman ▁pro cur ators , ▁at ▁least ▁for ▁a ▁very ▁short ▁span ▁of ▁time ". ▁ ▁Early ▁medieval ▁period ▁The ▁P ict s ▁reg ained ▁power ▁until ▁dispos s essed ▁by ▁the ▁Nor se ▁in ▁the ▁ 9 th ▁century , ▁with ▁the ▁possible ▁inter ruption ▁of ▁a ▁short ▁period ▁towards ▁the ▁beginning ▁of ▁the ▁ 6 th ▁century , ▁when ▁D ál ▁Ri ata ▁Ga els ▁may ▁have ▁established ▁a ▁foot ing ▁in ▁the ▁islands , ▁followed ▁by ▁C elt ic ▁mission aries ▁in ▁about ▁ 5 6 5 . ▁They ▁were ▁compan ions ▁of ▁Saint ▁Col um ba ▁and ▁their ▁efforts ▁to ▁convert ▁the ▁folk ▁to ▁Christian ity ▁seem ▁to ▁have ▁im pressed ▁the ▁popular ▁imagination , ▁for ▁the ▁names ▁of ▁several ▁islands ▁include ▁the ▁ep ith et ▁" P apa " ▁in ▁comm em oration ▁of ▁the ▁pre ach ers ▁old . Att ribution ? ▁ ▁Norwegian ▁rule ▁ ▁Vik ings ▁having ▁made ▁the ▁islands ▁the ▁headquarters ▁of ▁their ▁ag gress ive ▁exped itions ▁( car ried ▁out ▁ind iffer ently ▁against ▁their ▁own ▁Norway ▁and ▁the ▁coast s ▁and ▁is les ▁of ▁Scotland ), ▁Harold ▁H år f ag re ▁(" F air ▁H air ") ▁sub du ed ▁the ▁ro vers ▁in ▁ 8 7 5 ▁and ▁an nex ed ▁both ▁Or k ney ▁and ▁Sh et land ▁to ▁Norway . ▁They ▁remained ▁under ▁the ▁rule ▁of ▁Norwegian ▁ear ls ▁until ▁ 1 2 3 1 , ▁when ▁the ▁line ▁of ▁the ▁jar ls ▁became