Ecgfrith was killed during a campaign against his cousin, the King of the Picts Bridei map Beli, at a battle known as Nechtansmere to the Northumbrians, in Pictish territory north of the Firth of Forth. Bede recounts that Queen Eormenburh and Cuthbert were visiting Carlisle that day, and that Cuthbert had a premonition of the defeat. Ecgfrith's death threatened to break the hold of the descendants of Æthelfrith on Northumbria, but the scholar Aldfrith became king and the thrones of Bernicia and Deira remained united.