King Stephen had initially established himself well, displaying understanding and concern for his barons and maintaining good relations with the church, but Stephen’s inability to keep peace and order prompts the barons to rebel in 1138 favor of his cousin Matilda.

Matilda's half-brother, Robert of Gloucester, start the descent into civil war in England.

Robert is one of the most powerful Anglo-Norman barons, controlling estates in Normandy as well as the Earldom of Gloucester.

Robert renounces his fealty to the King and declares his support for Matilda, triggering a major regional rebellion in Kent and across the southwest of England, although Robert himself remains in Normandy.

Matilda has not been particularly active in asserting her claims to the throne since 1135 and in many ways it is Robert that takes the initiative in declaring war in 1138 In France, Geoffrey takes advantage of the situation by re-invading Normandy.

David of Scotland also invades the north of England once again, announcing that he is supporting the claim of Matilda to the throne, pushing south into Yorkshire.

Stephen rapidly responds to the revolts and invasions, focusing primarily on England rather than Normandy.

His wife Matilda is sent to Kent with ships and resources from Boulogne, with the task of retaking the key port of Dover, under Robert's control.

A small number of Stephen's household knights are sent north to help the fight against the Scots.