25 October - King Stephen dies

While staying in Dover, King Stephen suddenly became ill and died. He had agreed that Matilda's son Henry should become King upon his death. Henry was in Normandy at the time.

25 October - Death of Geoffrey Chaucer.

Geoffrey Chaucer died.

25 October - The Battle of Agincourt

The English army met the French army near the town of Agincourt. Although the English were outnumbered three to one, Henry used the local terrain to his advantage. The French cavalry were hit heavily by the English archers and French knights got bogged down in the wet fields. The French were defeated and Henry ordered that no prisoners should be taken apart from the extremely important knights who could be ransomed. The death toll amongst the French nobility was high.

25 October - Queen Margaret invades

Queen Margaret landed near Bamburgh Castle on the Northumbrian coast with a small army. The main castles in the area, Alnwick, Bamburgh and Dunstanburgh surrendered to the Queen.