▁in ▁ 8 6 7 , ▁and ▁the ▁kingdom ▁reached ▁then ▁its ▁maximum ▁extent : ▁it ▁received ▁parts ▁of ▁Norm andy , ▁Maine ▁and ▁An jou ▁and ▁the ▁Channel ▁Islands . ▁ ▁Brit t any ▁was ▁heavily ▁attacked ▁by ▁the ▁Vik ings ▁at ▁the ▁beginning ▁of ▁the ▁ 1 0 th ▁century . ▁The ▁kingdom ▁lost ▁its ▁eastern ▁territ ories , ▁including ▁Norm andy ▁and ▁An jou , ▁and ▁the ▁county ▁of ▁N antes ▁was ▁given ▁to ▁Ful k ▁I ▁of ▁An jou ▁in ▁ 9 0 9 . ▁However , ▁N antes ▁was ▁seized ▁by ▁the ▁Vik ings ▁in ▁ 9 1 4 , ▁and ▁was ▁eventually ▁liber ated ▁by ▁Alan ▁II ▁of ▁Brit t any ▁in ▁ 9 3 7 ▁with ▁the ▁support ▁of ▁his ▁god - bro ther ▁King ▁ Æ th el stan ▁of ▁England . ▁Alan ▁II ▁totally ▁exp elled ▁the ▁Vik ings ▁from ▁Brit t any ▁and ▁re created ▁a ▁strong ▁Bre ton ▁state . ▁He ▁paid ▁hom age ▁to ▁Louis ▁IV ▁of ▁France ▁( who ▁was ▁ Æ th el stan ' s ▁nep hew ▁and ▁had ▁returned ▁from ▁England ▁in ▁the ▁same ▁year ▁as ▁Alan ▁II ) ▁and ▁thus ▁Brit t any ▁ceased ▁to ▁be ▁a ▁kingdom ▁and ▁became ▁a ▁du chy . ▁ ▁Several ▁Bre ton ▁l ords ▁helped ▁William ▁the ▁Con quer or ▁to ▁in va de ▁England ▁and ▁received ▁large ▁est ates ▁there ▁( e . g . ▁William ' s ▁double - second ▁cousin ▁Alan ▁R uf us ▁and ▁the ▁latter