 The third and most serious problem concerned the king ’ s favourite , Piers Gaveston . Gaveston was a Gascon of relatively humble origins , with whom the king had developed a particularly close relationship . Among the honours Edward heaped upon Gaveston was the earldom of Cornwall , a title which had previously only been conferred on members of the royal family . The preferential treatment of an upstart like Gaveston , in combination with his behaviour that was seen as arrogant , led to resentment among the established peers of the realm . This resentment first came to the surface in a declaration written in Boulogne by a group of magnates who were with the king when he was in France for his marriage ceremony to the French king 's daughter . The so @-@ called Boulogne agreement was vague , but it expressed clear concern over the state of the royal court . On 25 February 1308 , the new king was crowned . The oath he was made to take at the coronation differed from that of previous kings in the fourth clause ; here Edward was required to promise to maintain the laws that the community " shall have chosen " ( " aura eslu " ) . Though it is unclear what exactly was meant by this wording at the time , this oath was later used in the struggle between the king and his earls . 
