The Lares familiares were a group of ancient Roman gods worshipped at lararia, the shrines that stood at the center of domestic religion. In this thesis, I revisit a century-long debate and present new evidence, derived from the close observation of the design and representational elements extant on the material remains of temples, tombs, and lararia, for the previously proposed but recently rejected theory that the Lares familiares were the spirits of deceased ancestors. In opposition to the approach of previous publications, I place archaeological, rather than textual, evidence from Roman Pompeii in the forefront to examine what new conclusions might be drawn. In Part 2, I consider the elements of formal design that may connect lararia not only with temple architecture, but also with tomb design. In Part 3, I analyze a series of representational elements that may suggest a similar visual connection between the Lares and the dead.