xvi Kal. Sept. (Aug. 17). NP.
PORT[UNALIA]. (MAFF. AMIT. VALL.)
TIBERINALIA. (PHILOC.)
FERIAE PORTUNO. (AMIT. ANT.)
PORTUNO AD PONTEM AEMILIUM. (AMIT. VALL. ALLIF.)
IANO AD THEATRUM MARCELLI. (VALL. ALLIF.)
Who was Portunus, and why was his festival in August? Why was it at the Pons Aemilius, and where was that bridge? Can any connexion be found between this and the other August rites? These questions cannot be answered satisfactorily; the scraps of evidence are too few and too doubtful. We have here to do with another ancient deity, who survives in the calendars only, and in the solitary record that he had a special flamen. This flamen might be a plebeian[[856]], which seems to suit with the character of other cults in the district by the Tiber, and may perhaps point to a somewhat later origin than that of the most ancient city worships.
There are but two or three texts which help us to make an uncertain guess at the nature of Portunus. Varro[[857]] wrote ‘Portunalia et Portuno, quoi eo die aedes in portu Tiberino facta et feriae institutae.’ Mommsen takes the portus here as meaning Ostia at the mouth of the Tiber, and imagines a yearly procession thither from Rome on this day[[858]]. This of course is pure hypothesis; but if, as he insists, portus is rarely or never used for a city wharf on a river such as that at Rome, we may perhaps accept it provisionally; but in doing so we have to yield another point to Mommsen, viz. the identity of Portunus and Tiberinus. In the very late calendar of Philocalus this day is called Tiberinalia, and from this Mommsen infers the identity of the two deities[[859]].
But it may be that the original Portunus had no immediate connexion either with river or harbour. We find a curious but mutilated note in the Veronese commentary on Virgil[[860]]: ‘Portunus, ut Varro ait, deus port[uum porta]rumque praeses. Quare huius dies festus Portunalia, qua apud veteres claves in focum add ... mare institutum.’ Huschke[[861]] here conjectured ‘addere et infumare,’ and inferred that we should see in Portunus the god of the gates and keys which secured the stock of corn, &c., in storehouses. Wild as this writer’s conjectures usually are, in this case it seems to me possible that he has hit the mark. If the words ‘claves in focum’ are genuine, as they seem to be, we can hardly avoid the conclusion that something was done to keys on this day; perhaps the old keys of very hard wood were held in the fire to harden them afresh[[862]]. It is worth noting that according to Verrius[[863]] Portunus was supposed ‘clavim manu tenere et deus esse portarum.’ This would suit very well with harvest-time, when barns and storehouses would be repaired and their gates and fastenings looked to—more especially as it is not unlikely that the word portus originally meant a safe place of any kind, and only as civilization advanced became specially appropriated to harbours[[864]]. This appropriation may have come about through the medium of storehouses near the Tiber; and it was long ago suggested by Jordan that these were under the particular care of Portunus[[865]].
If Portunus were really a god of keys and doors and storehouses, it would be natural to look for some close relation between him and Janus. But what can be adduced in favour of such a relation does not amount to much[[866]]; and it may have been merely by accident that this was the dedication-day of a temple of Janus ‘ad theatrum Marcelli’[[867]].