Gregory of Tours

Writer of the History of the Franks (primary source) and Bishop of Tours during the Merovingian period.

Personally knew 4 Merovingian kings, Sigebert I, Chilperic I, Guntram, and Childeber II

https://sourcebooks.fordham.edu/basis/gregory-hist.asp History of the Franks. 538 to 594

Liutprand of Cremona

Diplomat for the King of Italy and then for Otto I, primarily known for his time with the Byzantines. Also Bishop of Cremona. His first mission to Constantinople was great, but the second one was very hostile due to tensions between Otto and the basileus, Nicephorus.

http://medieval.ucdavis.edu/20A/Luitprand.html Report of his Mission to Constantinople, 968