In 1308, Edward's marriage to Isabella of France proceeded. Edward crossed the English Channel to France in January, leaving Gaveston as his "custos regni" in charge of the kingdom. This arrangement was unusual, and involved unprecedented powers being delegated to Gaveston, backed by a specially engraved Great Seal. Edward probably hoped that the marriage would strengthen his position in Gascony and bring him much needed funds. The final negotiations, however, proved challenging: Edward and Philip IV did not like each other, and the French king drove a hard bargain over the size of Isabella's dower and the details of the administration of Edward's lands in France. As part of the agreement, Edward gave homage to Philip for the Duchy of Aquitaine and agreed to a commission to complete the implementation of the 1303 Treaty of Paris.