▁after ▁ 7 1 1 , ▁although ▁the ▁northern most ▁portion ▁was ▁divided ▁between ▁several ▁Christian ▁states . ▁In ▁the ▁ 1 1 th ▁century , ▁and ▁again ▁in ▁the ▁th ir teenth , ▁the ▁Christian ▁kingdom s ▁of ▁the ▁north ▁gradually ▁drove ▁the ▁Muslim s ▁from ▁central ▁and ▁most ▁of ▁southern ▁I ber ia . ▁ ▁In ▁Italy , ▁independent ▁city ▁states ▁grew ▁aff lu ent ▁on ▁eastern ▁mar itime ▁trade . ▁These ▁were ▁in ▁particular ▁the ▁th al assoc ra cies ▁of ▁P isa , ▁Am alf i , ▁Gen oa ▁and ▁Ven ice . ▁ ▁Sc and in avia ▁ ▁From ▁the ▁mid - t enth ▁to ▁the ▁mid - 1 1 th ▁centuries , ▁the ▁Sc and in av ian ▁kingdom s ▁were ▁un ified ▁and ▁Christian ized , ▁resulting ▁in ▁an ▁end ▁of ▁Vik ing ▁ra ids , ▁and ▁greater ▁invol vement ▁in ▁European ▁politics . ▁King ▁C nut ▁of ▁Den mark ▁ruled ▁over ▁both ▁England ▁and ▁Norway . ▁After ▁C nut ' s ▁death ▁in ▁ 1 0 3 5 , ▁England ▁and ▁Norway ▁were ▁lost , ▁and ▁with ▁the ▁defeat ▁of ▁Val dem ar ▁II ▁in ▁ 1 2 2 7 , ▁Dan ish ▁pre domin ance ▁in ▁the ▁region ▁came ▁to ▁an ▁end . ▁Meanwhile , ▁Norway ▁extended ▁its ▁Atlantic ▁poss essions , ▁r anging ▁from ▁Green land ▁to ▁the ▁Is le ▁of ▁Man , ▁while ▁Sweden , ▁under ▁Bir ger ▁Jar l , ▁built ▁up ▁a ▁power - base ▁in ▁the ▁Balt ic ▁Sea