Were there any Frankish/French kings who probably had no extramarital sexual relations?

Question

I was listening to Dan Carlin's podcast about the start of Merovingian dynasty, and he made a snide quip about the early Merovingians (starting with Clovis) and even Carolingians not exactly being paragons of Christian morality - including having official concubines.

We also know that many later French kings in 16th+ century clearly had mistresses (I'm excluding Louis XIII who everyone and their grandmother thinks was homosexual or at least bi, and had male lovers even if he had no known female mistresses).

Were there any French kings who probably had no extramarital sexual relations? (e.g. who were renowned among their contemporaries for their "chastity," as opposed to merely not having proof to the contrary).

I'm doing this according to Catholic doctrine, so divorcing and re-marrying counts as "extramarital" - so Philip I the Amorous doesn't count even if he married Bertrade de Montfort.

Also, someone who was actually married and of an age/position to have extramarital affairs is a working assumption here.

Answer 1

Fortunately, Wikipedians maintain a list of French royal mistresses, so we can knock off a whole slew of Kings at once (link). The list starts with Clovis I and ends with Napoleon III: the A-Z of French royal infidelity.

Any king not on that list is a candidate for having been a faithful husband. I'll suggest that Saint Louis IX was among the most likely to have been faithful. Discussions of his sex life suggest that although he loved his wife and had eleven children with her, he was still pretty good with self-control:

If one were to pass judgment on the marital life of Louis IX, one could say without reservation that it fulfilled all the requirements made by Pope Piux XI in his encyclical on marriage, Casti connubii. It was a chaste marriage, in which there was no misuse of the marriage right . . . Ever since their youth they had faithfully practiced marital continence . . . The biographers explicitly report that they observed continence during the so-called "days of abstinence" in the liturgical year, in Advent and Lent, also on Friday and Saturday of each week, and, furthermore, for one day before and one day after the reception of Holy Communion . . . It goes without saying that sexual abstinence was also practiced in the marriage whenever the wife was pregnant . . .

After lots of Googling and Google book-searching, I haven't found any mention of courtesans, affairs, or mistresses associated with Louis IX. Given the amount of historiographical interest in Louis IX, and given that biographers were apparently familiar with his sex life, Louis IX seems as "probably chaste" as any of the other French kings left off that list.

Answer 2

King Louis VII was probably one such king. His first wife, Eleanor of Acquitaine (in)famously complained that he was "more of a monk than a man." When they got married (as teenagers), he donated her wedding gift, a valuable rock crystal vase, to the St. Denis Basilica (church).