The Anarchy

Near contemporary illustration of the Battle of Lincoln; Stephen (fourth from the right) listens to Baldwin of Clare orating a battle speech (left)

Date	1135–54
Location	England and Normandy
Result	Treaty of Wallingford: Stephen remains king, but with Henry as designated heir

Belligerents

Forces loyal to Stephen of Blois

Forces loyal to Empress Matilda & Henry Plantagenet

Commanders and leaders

Stephen of Blois
Matilda of Boulogne

Empress Matilda
Robert of Gloucester
Geoffrey Plantagenet
Henry Plantagenet

The Anarchy was a civil war in England and Normandy between 1135 and 1154, which resulted in a widespread breakdown in law and order. The conflict was a succession crisis precipitated by the accidental death of William Adelin, the only legitimate son of Henry I, in 1120. Henry's attempts to install his daughter, the Empress Matilda, as his successor were unsuccessful and on Henry's death in 1135, his nephew Stephen of Blois seized the throne with the help of Stephen's brother, Henry of Blois, Bishop of Winchester. Stephen's early reign was marked by fierce fighting with English barons, rebellious Welsh leaders and Scottish invaders. Following a major rebellion in the south-west of England, Matilda invaded in 1139 with the help of her half-brother, Robert of Gloucester.

Neither side was able to achieve a decisive advantage during the first years of the war; the Empress came to control the south-west of England and much of the Thames Valley, while Stephen remained in control of the south-east. The castles of the period were easily defensible, and much of the fighting was attritional in character, comprising sieges, raiding and skirmishing between armies of knights and footsoldiers, many of them mercenaries. In 1141 Stephen was captured following the Battle of Lincoln, causing a collapse in his authority over most of the country. However, on the verge of being crowned queen, Empress Matilda was forced to retreat from London by hostile crowds; shortly afterwards, Robert of Gloucester was captured at the rout of Winchester and the two sides agreed to swap their respective captives. Stephen then almost seized Matilda in 1142 during the siege of Oxford, but the Empress escaped from Oxford Castle across the frozen River Thames to safety.

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