Following the death of Henry I (William the Conqueror's younger son) the crown was supposed to go to his daughter Matilda. Unfortunately, before she could return to England from Anjou, cousin Stephen hopped over from France and had himself crowned in her place in 1135. This resulted in a civil war, precipitated by Matilda's return to England with a rebel army in 1139.

Things dragged on for ages, with neither party gaining a clear upper hand. Stephen wanted his son, Eustace, to succeed him - but when Eustace died unexpectedly, a deal was worked out allowing Stephen to hold the crown until his death, after which it passed to Matilda's son, Henry (II).