Æthelfrith of Northumbria had in 592 succeeded Hussa as king of Bernicia.
His accession possibly involves dynastic rivalry and the exile of Hussa's relatives.
Æthelfrith protects his borders in 603 by fighting and defeating the Scots king of Dalriada (Argyll) and the Britons of Strathclyde at Degasaston (Dawson Rig, Liddesdale?).
With Æthelfrith’s defeat of the Scots and Britons at Degsastan in 603, Angles now dominate central Britain from east to west below the Firth of Forth.