GENIO (Genius). — An exclusively Roman religious concept. Unlike the classical independent divine figures, the G. always belongs to persons, communities, places, or even gods: all of these have their own G. The G., however, is in every individual case a divinity. The documentation is relatively recent and does not permit us to establish whether originally the concept of the G. was restricted to one of the categories mentioned and, if so, to which one.
For the public cult of the G., there is evidence of an animal sacrifice in 218 B.C. The Genius populi Romani, Genius publicus, and Genius Urbia Romae frequently appear indistinctly in the tradition. A sanctuary of the public G. stood near the temple of Concordia; an annual sacrifice common to the public G., Fausta Felicitas, and Venus Victrix is documented for 9 Oct. From the 4th century A.D. ludi genialici (11–12 Feb.) are known. In domestic worship, the G. of the head of the family predominates. Its feast is the birthday of the paterfamilias. Bloodless sacrifices, especially unmixed wine, are offered to these G. Dependants swear by the G. of the head of the family. In representations, the G. appears as a young man, with a cornucopia and patera; in domestic paintings it seems to assume the features of the head of the family
himself; the theriomorphic expression of the G. is the serpent. The G. of the emperor has a public cult.
The word G. undoubtedly derives from the verbal root gen- (gignere, to beget): ancient and modern interpretation, however, oscillates among the various possibilities for explaining the connection. The G., inseparable from the person or thing to which it belongs, in any event represents its individual divine origin. While in some cases the G. is also attributed to women and goddesses, more often a distinction is made between the G. of the man and the Iuno of the woman.