So two questions. Firstly, how confident are historians that the Pope actually supported William the conqueror? Secondly, if it did why?
I mean Godwinson doesn't seem an especially pious man considering he didn't bother to ever have his marrage made offical in church but that was fairly common practice in England at the time. I guess William was a big cathedral builder and the like but I can't find any previous incidents of the Pope attempting to interfere with English succession and Harold had been elected by the Witan.
Firstly, how confident are historians that the Pope actually supported William the conqueror?
Put it simply, the majority of the current scholarship suppose he did, but not all.
it is actually based on the passage of William of Poitiers, a Chaplain of William (linked to the old, Latin text, on the papal grant of his banner to the duke in eve of the invasion.
English Translation is as following:
'At that time the see of St Peter at Rome was occupied by Pope Alexander [1061–73], a most worthy man who was obeyed and consulted by the universal Church, for he gave just and salutary replies … Seeking approval of this pope, whom he had informed of the business in hand, the duke received a banner with his blessing, to signify the approval of St Peter, by following which he might attack the enemy with greater confidence and safety. Also he had recently made a friendly pact with Henry [IV], emperor of the Romans, son of the emperor Henry [III] and grandson of Emperor Conrad [II], by the terms of which Germany would, if requested, come to his aid against any enemy. Svein, king of the Danes, also pledged his faith to him through ambassadors; but he was to show himself the faithful friend of the duke’s enemies, as you will see in reading in what follows of the harm he did …' (William of Poitiers, the Deeds of William the Conqueror, II-3, in: van Houts trans. 2000: 119).
The bulk of this work is said to be written between 1070 and 1077, and William of Poitiers himself did not participated in the expedition by person, though he could without doubt rely on the witnesses of other participants. Then, how we can evaluate the trustworthiness of this paragraph?
The current leading scholar of the Conquest, Garnett, seems to acknowledge these passages at least for the grant of banner (Garnett 2009: 41-45), and Bates follow his argument (Bates 1989: 83). On the other hand, Huscroft casts doubts on the accuracy of the paragraph in general, mainly on the ground of the unlikeliness of the approval from King Sweyn of the Danes (close to Godwine family) as well as still young King Henry IV of Germany (I'm also not sure why he was called as imperator romanorum in the 1070s: The date of his formal coronation as an emperor was in 1084) (Huscroft 2002: 121f.). He also notes the absence of the corresponding description in the oldest account of the Conquest, the Deed of the dukes of the Normans, William of Jumièges. Thus, personally I'm inclined for Huscroft's argument, papal intervention hypothesis is generally accepted.
Secondly, if it did why?
It would be rather simple if such an event really happened: Asked, especially possibly by way of the person who was close to him, at least in traditional historiography. And it would also meet his political goal to extend the papal influence further.
Pope Alexander II was originally born in Milan, Italy, and called Anselm of Baggio. One of the closest political ally of Duke William, Abbot (later archbishop of Canterbury) Lanfranc (d. 1089) also came from Italy. Lanfranc was also known as a famous scholar of the period, and historians have traditionally assume that the future pope, Anselm, was once a student of Lanfranc in Le Bec, Normandy, though the extant evidences are not so conclusive.
Since the 1050s the Papacy sought to extend its influence across Europe, or the ideal of reform, by way of the reform councils, often presided by the papal legates delegated from Rome, such as Legate Hildebrand (Pope Gregory VII in the future) (Cushing 2005: 84). It certainly seemed to Alexander a good opportunity when his former tutor asked the approval in exchange for the promise of later cooperation, if this event really occurred.
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