Proca or Procas was in the mythological history of Rome a king of Alba Longa.
He was the son of Aventinus Silvius and is said to have reigned 23 years. Ovid tells the story in the Fasti that the five- day-old infant was almost sucked out of strigae. Through the intervention of the Cardea but he will be saved.
Taking the reigns given by Dionysius of Halicarnassus with a back calculation from the traditional year of the founding of Rome is based, this corresponds to the years 819-796 BC The reign he bequeathed to his elder son Numitor. But his younger brother Amulius sales Numitor, killed his son and made his daughter Rhea Silvia to Vestal.
- Augustine City of God 18, 21
- Dionysius of Halicarnassus Antiquitates Romanae 1, 71
- Ovid Metamorphoses 14, 609-621. Fasti 4 Praefatio
- Livy 1, 3
- Virgil Aeneid 6, 767