Isabella married twice more after William's death, with her husbands Geoffrey de Vere and William Botorel being lords of Clun Castle by virtue of marriage, but on her death in 1199 the castle passed to her son from her first marriage, the second William Fitz Alan.Brown, p. 93; Suppe, 2001, p. 210. In doing so, Isabella created the combined lordship of neighbouring Oswestry and Clun, the beginnings of what would become a powerful noble family. William built the tall, off-centre Norman keep that dominates the site today, blending a defensive fortification with the beginnings of a more luxurious style of living. William had been with King Richard I during the building of Château Gaillard in Normandy and it would seem that the distinctive circular towers William built to defend the new keep at Clun were based on those at Gaillard. The result was echoed in Shropshire, on a smaller scale, in the fortified tower-houses at Upper Millichope and Wattlesborough, whilst several generations later the trend would result in Stokesay Castle.Emery, p. 576.
