During the civil war of the Anarchy, fought between the factions of Stephen of England and the Empress Matilda, both sides built a number of new castles to defend their territories and act as bases for expansion, typically motte and bailey designs such as those at Winchcombe, Upper Slaughter, or Bampton by the Empress's followers. Similarly, Stephen built a new chain of fen-edge castles at Burwell, Lidgate, Rampton, Caxton, and Swavesey – all about six to nine miles (ten to fifteen km) apart – in order to protect his lands around Cambridge.