The effect of the attainder was to terminate the Barony of Okehampton (creation 1299), so that the Earldom inherited from the Redvers family was in abeyance,[citation needed] passing laterally to the descendants of Courtenay's sisters [4] The new King, Edward IV, marched north and sealed his reign with the bloody victory at the Battle of Towton, following which his brother was beheaded.

[6] Following Edward IV's return to England to challenge the restored Lancastrian regime in 1471, Courtenay was in London with Henry VI and Edmund Beaufort, Duke of Somerset, while King Edward gathered troops in the East Midlands and manoeuvred against the Lancastrians under Richard Neville, Earl of Warwick.

However, Somerset and Courtenay left the city to rendezvous in the south-west of England with Margaret of Anjou and her son, Edward of Westminster, Prince of Wales, who were returning from France.

Queen Margaret landed in England two days later, and met Devon and Somerset in Cerne Abbey,[8] where they "assured her that their cause was far from lost".

[11] Marching to unite with other Lancastrian forces being assembled in the West Midlands and Wales, they were intercepted by King Edward IV and brought to battle at Tewkesbury on 4 May 1471.