Timespan
The Legend of the Four Sons of Aymon is placed in the time of the reign of Charlemagne, who was born in either 742 or 747.
Charlemagne died in 814 and so he may have become at the most 72 years old.
The Legend refers to Charles as 'an old man', even when Aymon claims his reward. Of course this is not possible, as Aymon is referred to as Charles' uncle.
When we take Son of Aquitaine as point of reference (he is mentioned in Pomer's family tree, with the suggestion that he is born after 750, we must assume that his daughter was born after 770 and married Renaud later than 780. This narrows down the legend to between the years 770 and 814, at least where the part of Renaud is concerned.
People
Aymon Duke of Burgundy
Aymon is in the legend known as an uncle of Charlemagne. This places him at the same age-level more or less as Charles' father Pepin the Short. Pepin was born in 714. Assuming that Aymon was of the same age we could also assume that Aymon fought at the side of Charles Martel, his father. It is a historical known fact that Charles Martel actually made Aymon Duke of Burgundy, although if Charles Martel did that after the battle of Poitiers it must have been done between 732 and 739 in which year Charles Martel died, only probably 53 years old. (Not an old king either). This places the time-span of the legend between 730 and 814. Why Aymon lost his title of Duke of Bourgundy to be exchanged for the lesser title of Duke of Dordogne - the Dordogne was not a fertile place at all in those days and the capital of the dukedom Albi was not impressive, may be found in the relationship of Aymon with Charles Martel's son Pepin, who must have been of approximately the same age as Aymon and in some way or another his half-brother. It is not inconceivable that Aymon was one of Charles Martel's bastard children, and if he has been e.g. older than Pepin there might have been a lot of jealousy among them. Herein may lie the seeds of the hatred between uncle Aymon and nephew Charlemagne.
It is told that Aymon was not a young man anymore when he marries Charles' sister Aye.
Adelheid, Rothaid, sister of Charlemagne
Pepin the Short is not known to have strayed from his wife Bertrada of Laon. He had a second daughter by the name of Adelheid (Adelaide) Rothaid in the annals, born before Charles and who disappears from history after her sixth year. The oldest daughter's name was Rothaid(after 740). One of those daughters supposedly died early. A guess would be that it was the oldest daughter Rothaid as Adelaid gets the addition of her name. The Historie van den Vier Heemskinderen was written in the last part of the 13th century, the age that one knew of Aye of Avignon, the Beautiful, fictional daughter of Doon de Mayence, also supposedly named as Aymon's father in other legends. It is possible that the names became mixed up in history.
If Adelaide or Aye marries Aymon at her twelfth year we look at the years 756 till 760. Aymon will be about 36 years old then, not truly very old, but a seasoned warrior. When he faces a 16 year old Renaud for the first time as told in the story, it must be about the year 773. Aymon might be in his fifties by that time.
Son d'Aquitaine
The name appears in Jacob van Maerlant's Historie van de Vier Heemskinderen when the main character of the legend marries Claire, the daughter of Son the Duc of Aquitaine and receives the castle of Montalbaen or Montauban in the South of France which was in those days probably part of the Aquitaine Dukedom.
The name Son is not a usual one, the French dictionary of names only knows the Greek name Sonia as closest to the name Son. Sonia means wisdom. Therefore the name has much meaning if it comes to historical research. The existence of Son d'Aquitaine is an important one as it relates to the marriage of Renoud or Renaud de Montauban and so the time of the legend can be better calculated. Son d'Aquitaine shows up in the Pomer Family tree of the World Roots website. He is the Son of Waifer of Aquitaine, whose father is the famous Odo of Aquitaine. According to the Pomer Family Trees Son must be born after the year 750, which makes him younger than Charlemagne.
Son of Aquitaine was bearing a heavy legacy: Pepin the Short took his father Waifer's title of King of Aquitaine away from him to bestow it on his infant son Carloman. Son was allowed to stay either count or duke. His son 'Loup' Centulus became count of Gascogne that was at the time incorporated in the Aquitaine Kingdom. This makes the political reasons clear why Renaud and his brothers first flee to the court of Loup of Gascongne and later are very cordially received by Son d'Aquitaine, when one looks at the adage 'the enemies of my enemy are my friends'. Son must have been very impressed with Renaud to seek his support in giving his daughter Claire to wife to Renaud and to give him the in those days important castle of Montauban as his wedding-present.
Loup de Gascogne
The Historie of de Vier Heemskinderen refers to King Loup of Gascogne (also Lupo). Research in The Pomer Family Tree shows us that he was actually a son of Son of Aquitaine, and bears the title of 'comte' or Count. This means he must have been of about Renaud's age with a span of ten years or more. It is true that Son's father Waifer lost the throne of Aquitaine to Pepin the Short. If Son d'Aquitaine became duke, his oldest son Loup may very well have gotten the title of Count of Gascogne that was in those days supposed to be part of the Aquitaine Kingdom. The name Loup means wolf in French and is of course very suitable in the legend to play the very bad man who betrays Renaud and his brothers to Charlemagne.
Renaud of Montauban
The question of whether Renaud is the same as Roland in the Chanson de Roland has spread through literature for some time. The Chanson de Roland took place at the Battle of Roncevalles in 778. In those days Charlemagne was only in his thirties and so Renaud must have been a teenager. This means it would be reasonable to accept the fact that Renaud and Roland were not one and the same person.
Where there is smoke there is fire?
Even with some main characters coming closer because they indeed have lived in history and more importantly at the same time as the legend's timespan it does not prove that Renaud and his brothers have truly existed, until direct evidence to the matter is found in history.
Pomer family trees
Son d'Aquitaine
http://worldroots.com/ged/pomer/dat315.html#1 Aquitaine Son d' Birth after 750; Gender: male; Father: Waifer of Aquitaine Waiofer d'Aquitaine, Duc, born after 700, death 768. Children: Aquitaine.
Loup de Casgogne
http://worldroots.com/ged/pomer/dat313.html#4 As in Pomer's family tree
Adelheid Rothaid
http://worldroots.com/ged/pomer/dat83.html#1 Sister to Charlemagne as in Pomer's family tree
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