 Blagge was joint commissioner for the musters for the Scottish campaign of that year, with Sir John Holcroft, a Lancashire landowner.This was a part of the war known as the Rough Wooing that culminated in the Battle of Pinkie Cleugh on 10 September.It seems likely that Blagge served throughout and he must have impressed Protector Somerset, who knighted him at Roxburgh, returning from the victorious campaign, between 18 and 25 September 1547.