Despite the rather shaky grounds on which accusations of English ecclesiastical disloyalty were founded, this was the reason for the invasion which was submitted to the Pope. It was probably something of an afterthought for William's plan, and certainly neither William nor Lanfranc were in a position to judge the English church. Yet the excuse was precisely what the invaders—and the Pope—needed to further their cause, as Howarth says:
:To William, it gave a chance of solving the problem of raising an army: he could promise land and booty to men who took part, but in a holy war the church could promise something more—salvation. To Lanfranc, it gave a chance to offer the Holy See an expansion of power it had been seeking in vain... Lanfranc could therefore ask for papal blessing of William's invasion and offer something in return: William's claim could be submitted to the judgement of the Pope. This would be the first time a pope had been asked to adjudicate a disputed royal succession, and would create a precedent of enormous importance to [PopeCardinal] Hildebrand... [who]And the present Pope, as it happened, had once been [Lanfranc's] student at [the monastic college of] Bec (p. 101).
A Hildebrand had previously been at the head of efforts to disentangle the election of popes from secular politics, thus bolstering the power and solidity of the papacy. (He was eventually elected pope, styled Pope Gregory VII, and is a saint in the [[Roman Catholic Church]].) Such an opportunity to put the papacy over secular politics could not be missed. Being the most skilful politician at the Vatican, he saw to it that a papal court was held in Rome ("without the slightest reference to the facts," says Howarth on p. 102) at which Harold was entirely unrepresented. As Howarth says:
:It is not recorded whether he was invited to send an advocate, but it is very unlikely. To ride from Rome to Bosham [where Harold was in England] and back again to Rome suggests a month on the road, and nobody was prepared to waste as much time as that. If he had been invited, he and the witan would certainly have answered, quite correctly, that the choice og a King of England had nothing to do with the Pope (p. 102).