The dukedom of Lancaster is a former English peerage, created three times in the Middle Ages, which finally merged in the Crown when Henry V succeeded to the throne in 1413.

The second creation was on 13 November 1362, for John of Gaunt, 1st Earl of Richmond and third surviving son of King Edward III.

Later that same year Bolingbroke usurped the throne of England from Richard II, becoming Henry IV, at which point the dukedom merged in the Crown.

It was customary at formal dinners in the historic county boundaries of Lancashire and in Lancastrian regiments of the armed forces for the Loyal Toast to be announced as "The King, Duke of Lancaster".

[citation needed] Traditionally in Lancashire, the national anthem was sung as "God save our gracious King, long live our noble Duke",[3][better source needed] as it is each Sunday morning in the Savoy Chapel in London, a church attached to the Duchy.