[2] Brian became a close friend of Robert, 1st Earl of Gloucester, Henry I's illegitimate son, and the two remained longstanding allies.
[citation needed] Brian held the honour of Wallingford by marriage, and his extensive estates in the counties of Berkshire and Wiltshire ran from the Chilterns to the Thames.
Although Stephen's forces repeatedly besieged Wallingford Castle, they failed to take the fortification and had to retreat as it had been reinforced by Brian.
Wallingford Castle under Brian fitz Count was considered impregnable, not just because of the fortifications but also due to the large body of fighting men he had gathered together.
[4] [b] His castle of Wallingford was the easternmost point of the Angevin defences in the Thames valley[7] and it held off King Stephen's forces for over thirteen years.