In Vergilium Commentarius
Maurus (Marius) Servius Honoratus
AB AETHERIO VENIT SATVRNVS OLYMPO: hoc dicit secundum poeticum morem; nam Saturnus rex fuit Cretae, quem Iuppiter filius bello pepulit. Hic fugiens ab Iano rege, qui urbem habuit, ubi nunc Ianiculum, est susceptus, qui regnabat in Italia. Quem cum docuisset usum vinearum et falcis et humaniorem victum, in partem est admissus imperii et sibi oppidum fecit sub clivo Capitolino, ubi nunc eius aedes videtur.
From lofty Olympus Saturn came: he says this according to poetic custom; for Saturn was king of Crete, whom Jupiter his son drove out in war. Fleeing, he was received by King Janus, who held the city, where the Janiculum now is, who was ruling in Italy. When he had taught him the use of vines and sickles and a more human way of life, he was admitted into a share of the rule, and he built a town for himself at the foot of the Clivus Capitolinus, where now his temple is seen.
Translation by Jane W. Crawford, © 2001.