Even as late as the third quarter of the 15th C, the etymological origin of the name was still known. In RCCaetani6, 2720, the same man is recorded as both Rubeus and Russius (cf. Rubeus).
Cite as: S.L. Uckelman. "Rosso". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2017, no. 1. http://dmnes.org/2017/1/name/Rosso.