Lupercalia was a very ancient, possibly pre-Roman pastoral festival, observed on February 13 through 15 to avert evil spirits and purify the city, releasing health and fertility. Lupercalia subsumed Februa, an earlier-origin spring cleansing ritual held on the same date, which gives the month of February (Februarius) its name.
The Lupercalia festival was partly in honor of Lupa, the she-wolf who suckled the infant orphans, Romulus and Remus, the founders of Rome, explaining the name of the festival, Lupercalia, or "Wolf Festival." The festival was celebrated near the cave of Lupercal on the Palatine Hill (the central hill where Rome was traditionally founded), to expiate and purify new life in the Spring.
The rites were directed by the Luperci, the "brothers of the wolf (lupus)", a corporation of sacerdotes (priests) of Faunus, dressed only in a goatskin. The festival began with the sacrifice by the Luperci of two male goats and a dog. Next two young patrician Luperci were led to the altar, to be anointed on their foreheads with the sacrificial blood, which was wiped off the bloody knife with wool soaked in milk, after which they were expected to smile and laugh.
The sacrificial feast followed, after which the Luperci cut thongs from the skins of the animals, which were called februa, dressed themselves in the skins of the sacrificed goats, in imitation of Lupercus, and ran round the walls of the old Palatine city, the line of which was marked with stones, with the thongs in their hands in two bands, striking the people who crowded near. Girls and young women would line up on their route to receive lashes from these whips. This was supposed to ensure fertility, prevent sterility in women and ease the pains of childbirth.

LET THE WHIPPINGS BEGIN!

http://en.wikipedia.org/wiki/Lupercalia
http://penelope.uchicago.edu/Thayer/E/Roman/Texts/secondary/SMIGRA*/Lupercalia.html