Death of Henry I sparks the succession crisis

King Henry I of England died on 1 December 1135 at Lyons-la-Forêt in Normandy, reportedly after eating a large quantity of lampreys against his physicians' advice. Despite having twice compelled his barons to swear oaths recognizing his daughter Matilda as heir, Henry's death set off a rapid and dramatic succession crisis.

Matilda, pregnant and in Anjou at the time, was in no immediate position to cross to England and assert her claim. Her cousin Stephen of Blois, who had himself sworn the 1126 oath, moved swiftly, crossing the Channel and having himself crowned king in London within weeks, with the support of key barons and the Church, who balked at accepting a female ruler, particularly one married to the resented Angevins.

This betrayal of the succession oaths ignited the prolonged civil war later termed 'the Anarchy' (a term coined by Victorian historians to describe the ensuing near two decades of conflict, lawlessness, and political fragmentation in England). Henry I's death thus stands as the hinge point of Matilda's life: it transformed her from an heir-designate into a contested claimant who would spend the next two decades fighting — through both diplomacy and open warfare — to reclaim what she and her supporters regarded as her rightful inheritance.