Roman/Latin demigod, son of Vulcan; founder of Praeneste (modern Palestrina, ca. 35 km southeast of Rome — one of the principal Latin League cities). Conceived when a spark from the hearth fire (scintilla de foco) entered the womb of one of the Depidii sisters as she sat by the fire — the canonical Vulcan-paternity-by-fire pattern that parallels the Servius Tullius Vulcan-paternity tradition (Dion. Hal. 4.2; Pliny, NH 36.204). Born and exposed near the temple of Jupiter; recovered by maidens going to fetch water. Raised among shepherds in the wild Latin uplands. Gathered companions from the surrounding shepherd-bands and led them to the upland site that became Praeneste. At a public assembly disputing his divine paternity, fire encircled Caeculus without harming him — the canonical paternal-recognition-by-fire-test that confirmed the Vulcanian inheritance and established his legitimacy as founder-king. Led the Praenestine contingent in the war against Aeneas, alongside the other Italian kings (Mezentius, Turnus, Lausus, Camilla); Vergil names him in the Italian-allies catalogue at Aeneid 7.678-681 — the late-foundational-figure-as-Italian-ally archetype. Praeneste preserved the Caeculus founder-cult through the imperial period; the Sanctuary of Fortuna Primigenia (built ca. 110 BCE, the largest Hellenistic-Italian temple complex) became the major religious center of Praeneste and absorbed the Caeculus-foundation tradition into the broader Praenestine cult-system. The hearth-spark conception, fire-recognition, and shepherd-band foundation form the structurally-distinctive Vulcanian-Italian founder-figure pattern.