A demon whose worship was linked with that of Diana, in the sacred woods surrounding Nemi (Aricia). The fact that horses were not allowed to enter this wood gave rise to the belief that Virbius was none other than HIPPOLYTUS, son of Theseus, who had been killed by his horses, revived by Asclepius, and transported by Artemis to Italy. This interpretation was supported by a pun, breaking Virbius up into vir (man) and bis (twice): thus, he who had been a man twice, and this was seen as an allusion to the resurrection of the hero.
{E2 DICTIONARY OF CLASSICAL MYTHOLOGY}