▁was ▁a ▁member ▁of ▁the ▁ins ular ▁U í ▁Í ma ir . ▁ ▁There ▁is ▁uncertainty ▁surrounding ▁Mac cus ' ▁name . ▁Although ▁the ▁nin ete enth - century ▁edition ▁of ▁the ▁sevent e enth - century ▁Ann als ▁of ▁the ▁Four ▁Masters ▁refers ▁to ▁him ▁as ▁, ▁suggesting ▁that ▁the ▁G ael ic ▁ ▁is ▁a ▁form ▁of ▁the ▁Old ▁Nor se ▁— its elf ▁a ▁borrow ing ▁of ▁the ▁Latin ▁— the ▁oldest ▁manuscript ▁forms ▁of ▁this ▁source ▁show ▁that ▁the ▁recorded ▁name ▁was ▁actually ▁an ▁abbre vi ated ▁form ▁of ▁Mac cus . ▁Besides ▁this ▁m istr ans cription , ▁Mac cus ▁is ▁not ▁accord ed ▁the ▁name ▁ ▁by ▁any ▁historical ▁source , ▁and ▁his ▁name ▁is ▁unlikely ▁to ▁refer ▁to ▁it . ▁Mac cus ' ▁name ▁may ▁instead ▁by ▁of ▁G ael ic ▁origin . ▁ ▁Ir ruption ▁into ▁the ▁Irish ▁Sea ▁region ▁ ▁The ▁Me ic ▁Ara ilt ▁first ▁appear ▁on ▁record ▁in ▁the ▁Irish ▁Sea ▁in ▁the ▁ 9 7 0 s . ▁The ▁power ▁of ▁family ▁seems ▁to ▁have ▁been ▁cent red ▁in ▁the ▁Is les , ▁ ▁and ▁may ▁have ▁been ▁based ▁upon ▁control ▁of ▁the ▁important ▁trade ▁routes ▁through ▁the ▁Irish ▁Sea ▁region . ▁If ▁the ▁Me ic ▁Ara ilt ▁were ▁indeed ▁cent red ▁in ▁the ▁Heb rides , ▁the ▁family ' s ▁apparent ▁amb ition ▁to ▁secure ▁control ▁of ▁Mann ▁could ▁account ▁for ▁its ▁campaign ing ▁against ▁the ▁Wel sh ▁on ▁Ang les ey . ▁The ▁latter ▁island ▁was ▁the ▁traditional