There is very scant evidence of what happened during this event and the only contemporary account comes from William of Worcester in his book Annales rerum Anglicarum, in which he stated (Translation from Latin): In December Parliament adjourned.
[1]Somerset had marched from Corfe Castle, Dorset[2] and was heading north towards the rest of the Lancastrian army which had been based in Hull before moving onto Pontefract.
The most plausible reason however would have been to check on the Lancastrian forces situated around the town or for retribution towards Worksop Manor, where the Earl of Shrewsbury and his younger brother Christopher Talbot had been killed at the Battle of Northampton on 10 July that year.
(Christopher Talbot was murdered in 1443 at Caus Castle) Revenge was certainly in order as the Earl of Shrewsbury had been given Richard of York's land in Wakefield in 1459.
[5] Also Richard of York had a personal vendetta against the Beauforts, ever since the 2nd Duke of Somerset's disastrous handling of the final campaigns of the Hundred Years' War.