The Lupercalia was an annual Roman festival held on a.d. XV Kal. Mar. ‡ to honour Faunus, god of fertility and forests. Justin Martyr identified Faunus as Lupercus, the one who wards off the wolf, but his identification is not supported by any earlier classical sources. The festival was celebrated near the cave of Lupercal on the Palatine (one of the seven Roman hills), to expiate and purify new life in the Spring. This festival's origins are older than the founding of Rome.
"Lupercalia, of which many write that it was anciently celebrated by shepherds, and has also some connection with the Arcadian Lycaea. At this time many of the noble youths and of the magistrates run up and down through the city naked, for sport and laughter striking those they meet with shaggy thongs. And many women of rank also purposely get in their way, and like children at school present their hands to be struck, believing that the pregnant will thus be helped in delivery, and the barren to pregnancy." - Plutarch, Life of Caesar 61
"So we worship the god, and the priest performs The rites the Pelasgians brought in the ancient way. Why, you ask, do the Luperci run, and since it's their custom, This running, why do they strip their bodies naked? The god himself loves to run swiftly on the heights, And he himself suddenly takes to flight. The god himself is naked, and orders his servants naked, Since anyway clothes were not suited to that course. They say the Arcadians had their land before the birth Of Jove, and their race is older than the moon. They lived like beasts, lives spent to no purpose: The common people were crude as yet, without arts. They built houses from leafy branches, grass their crops, Water, scooped in their palms, was nectar to them. No bull panted yoked to the curved ploughshare, No soil was under the command of the farmer. Horses were not used, all carried their own burdens, The sheep went about still clothed in their wool. People lived in the open and went about nude, Inured to heavy downpours from rain-filled winds. To this day the naked priests recall the memory Of old customs, and testify to those ancient ways... A she-wolf, which had given birth to her whelps came, wondrous to tell, to the abandoned twins [Romulus and Remus] ...She halted and fawned on the tender babes with her tail, and licked into shape their two bodies with her tongue ...fearless, they sucked her dugs and were fed on a supply of milk that was never meant for them. The she-wolf (lupa) gave her name to the place, and the place gave their name to the Luperci. Great is the reward the nurse has got for the milk she gave." - Ovid , Fasti II
"It is said that the festival of the Lupercalia, which is still observed, was even in those days celebrated on the Palatine hill. This hill was originally called Pallantium from a city of the same name in Arcadia; the name was afterwards changed to Palatium. Evander, an Arcadian, had held that territory many ages before, and had introduced an annual festival from Arcadia in which young men ran about naked for sport and wantonness, in honour of the Lycaean Pan, whom the Romans afterwards called Inuus. The existence of this festival was widely recognised, and it was while the two brothers were engaged in it that the brigands, enraged at losing their plunder, ambushed them. Romulus successfully defended himself, but Remus was taken prisoner and brought before Amulius, his captors impudently accusing him of their own crimes. The principal charge brought against them was that of invading Numitor's lands with a body of young men whom they had got together, and carrying off plunder as though in regular warfare. Remus accordingly was handed over to Numitor for punishment." - Livy, History of Rome 1.5
"But Aelius Tubero, a shrewd man and careful in collecting the historical data, writes that Numitor's people, knowing beforehand that the youths were going to celebrate in honour of Pan the Lupercalia, the Arcadian festival as instituted by Evander, set an ambush for that moment in the celebration when the youths living near the Palatine were, after offering sacrifice, to proceed from the Lupercal and run round the village naked, their loins girt with the skins of the victims just sacrificed. This ceremony signified a sort of traditional purification of the villagers, and is still performed even to this day." - Dionysius of Halicarnassus, Roman Antiquities 1.80
"In support of this story, Varro relates others no less incredible about that most famous sorceress Circe, who changed the companions of Ulysses into beasts, and about the Arcadians, who, by lot, swam across a certain pool, and were turned into wolves there, and lived in the deserts of that region with wild beasts like themselves. But if they never fed on human flesh for nine years, they were restored to the human form on swimming back again through the same pool. Finally, he expressly names one Demaenetus, who, on tasting a boy offered up in sacrifice by the Arcadians to their god Lykaios according to their custom, was changed into a wolf, and, being restored to his proper form in the tenth year, trained himself as a pugilist, and was victorious at the Olympic games. And the same historian thinks that the epithet Lykaios was applied in Arcadia to Pan and Jupiter for no other reason than this metamorphosis of men into wolves, because it was thought it could not be wrought except by a divine power. For a wolf is called in Greek lykòs, from which the name Lykaios appears to be formed. He says also that the Roman Luperci were as it were sprung of the seed of these mysteries." - Augustinius of Hippo, City of God 18.17
"After [Saturn], third in descent, they say that Faunus was king, in whose time Evander came into Italy from Pallanteum, a city of Arcadia, accompanied with a small band of his countrymen, to whom Faunus kindly gave land, and the mountain which he afterwards called Palatium. At the foot of this mountain he built a temple to the Lykaian god, whom the Greeks call Pan, and the Romans Lupercus, the naked statue of the deity being covered with a goat-skin, in which dress the priests now run up and down during the Lupercalia at Rome." - Justin, Epitome 43.6ff
"There was added to these causes of offence his insult to the tribunes. It was, namely, the festival of the Lupercalia, of which many write that it was anciently celebrated by shepherds, and has also some connection with the Arcadian Lycaea. At this time many of the noble youths and of the magistrates run up and down through the city naked, for sport and laughter striking those they meet with shaggy thongs. And many women of rank also purposely get in their way, and like children at school present their hands to be struck, believing that the pregnant will thus be helped to an easy delivery, and the barren to pregnancy." - Plutarch, Life of Iulius Caesar 61.1-2
The religious ceremonies were directed by the Luperci, the "brothers of the wolf", priests of Faunus, dressed only in a goatskin. During Lupercalia, a dog and two male goats were sacrificed. Two patrician youths were anointed with the blood, which was wiped off with wool soaked in milk, after which they were expected to smile and laugh. The Luperci afterwards dressed themselves in the skins of the sacrificed goats, in imitation of Lupercus, and ran round the Palatine Hill with thongs cut from the skins in their hands. These were called Februa. Girls would line up on their route to receive lashes from these whips. This was supposed to ensure fertility. The name of the month of February is derived from the Latin februare, "to purify", meant as one of the effects of fever, which has the same linguistic root.
"You did see that on the Lupercal, I thrice presented him a kingly crown, Which he did thrice refuse." - William Shakespeare: Mark Antony speaking of Caesar in "Julius Caesar" III.ii
Tradition states that on this day in 44 B.C., Marcus Antonius offered Caesar a king's crown to rule over Rome, but Caesar refused, saying "Only Iuppiter is king in Rome."