 It was erected in 1138 and being in the corner of the city walls, could easily contact the outside world.Nevertheless, the Angevins put strong pressure on its defenders.Queen Matilda quickly assembled an army of relief that included mercenaries hired by Bishop Henry, a levy of the queen's feudal tenants from the County of Boulogne, the nearly 1,000-strong London militia, William of Ypres' Flemish mercenary cavalry and other supporters of Stephen.