Bertha of Toulouse - NN Mistress, only possibly Bertha

Bertha appears to be only one of the possibilities for the name of Bernard's mother. See Medlands Discussion below:

Mistress (1): (from [795]) --- . Thegan's Vita Hludowici Imperatoris records that Pepin's son Bernard was born "…ex concubina"[624]. However, other sources do not refer to the fact that he was illegitimate. The question is not beyond doubt. Assuming that he was illegitimate, the name of King Pepin's mistress is not known. Settipani quotes a name list in the Liber confraternitatum augiensis which reads "Karolus maior domus, Pippin rex, Karlomannus maior domus, Karolus imperator, Karolus rex, Pippin rex, Bernardus rex, Ruadtrud, Ruadheid, Svanahild regina, Bertha regina, Hiltikart regina, Fastrat regina, Liutkart regina, Ruadheid, Hirminkar regina"[625]. He makes the obvious links between "Karolus maior domus…Svanahild regina", "Pippin rex…Bertha regina" and "Karolus imperator…Hiltikart regina, Fastrat regina, Liutkart regina", deducing that the last named "Ruadheid" must be linked logically to "Pippin rex". However, this link is not inevitable. It is based on three assumptions: firstly that the second "Pippin rex" was Pepin King of Italy (he is the most likely candidate, but it could also be Pepin King of Aquitaine, son of Emperor Louis I); secondly that there are no female names linked either to "Karolus rex" or to "Bernardus rex", which cannot be proved; and thirdly, that all the females listed were partners of the males listed, which is certainly not the case in view of the absence of Emperor Louis I "le Pieux" who is assumed to be the husband of "Hirminkar regina". Rösch suggests Bertha as the possible name of King Pepin's wife, citing Stromeyer[626]. Settipani suggests that she was a close relative of Adalhard Abbé de Corbie and his half-brother Wala to explain the appointment of the former as regent for her son Bernard King of Italy in 813.

King Pepin had one illegitimate child by Mistress (1):

1. BERNARD ([797]-Milan 17 Aug 818, bur Milan, San Ambrosio). Thegan's Vita Hludowici Imperatoris names "Bernhardus filius Pippini ex concubina"[627]. He was confirmed 11 Sep 813 at Aix-la-Chapelle as BERNARD I King of Italy.

http://fmg.ac/Projects/MedLands/ITALY,%20Kings%20to%20962.htm#Pepin...