Many modern Pagans observe festivals and celebrations that originated with the classical Roman calendar. Because early Roman Paganism was tied so closely to daily life, it wasn't uncommon for people to celebrate different gods and goddesses every month or even weekly. The ancient Romans honored a wide variety of gods, and many are still worshipped today by Roman reconstruction groups. Even if your path isn’t specifically rooted in Roman religion, you can still observe these holidays, many of which were based upon seasonal or agricultural markers.
Februalia was a period of sacrifice and atonement, invovling offerings to the gods, prayer, and sacrifices. While it often focused on purification, it was also considered a festival of fire. February was dedicated to Februus, a god not unlike Dis or Pluto, because it was the month in which Rome was purified by making offerings and sacrifices to the gods of the dead.
Originally, this week-long party honored the god Faunus, who watched over shepherds in the hills. The festival also marked the coming of spring. Later on, it became a holiday honoring Romulus and Remus, the twins who founded Rome after being raised by a she-wolf in a cave. Eventually, Lupercalia became a multi-purpose event: it celebrated the fertility of not only the livestock but people as well.
The holiday of Matronalia was celebrated each year at the beginning of March. This annual "festival of women" was held in honor of Juno Luciana, a goddess who watched over married women and those in childbirth. She was in charge of newborn infants, and a woman in labor might make offerings to her so that she would have a safe delivery of a healthy child.
Flora was the goddess of spring flowers and vegetation, and one of many fertility goddesses. In fact, she was so well respected as a fertility deity that she was often seen as a the patron deity of Roman prostitutes. It was believed that a good festival ensured that Flora would protect the blooming flowers around the city.
In ancient Rome, Bona Dea was a goddess of fertility. In an interesting paradox, she was also a goddess of chastity and virginity. Honored originally as an earth goddess, she was an agricultural deity, and was often invoked to protect the area from earthquakes. Unlike many Roman goddesses, Bona Dea seems to have been particularly honored by the lower social classes. Slaves and plebian women who were trying to conceive a child might make offerings to her in hopes of being granted a fertile womb. In addition to the spring celebration, in some areas she was also honored in December.
This festival honored Vesta, the Roman goddess who guarded virginity. She was sacred to women, and alongside Juno was considered a protector of marriage. The Vestalia was celebrated from June 7 to June 15, and was a time in which the inner sanctum of the Vestal Temple was opened for all women to visit and make offerings to the goddess.
Pomona was a Roman goddess who was the keeper of orchards and fruit trees. Unlike many other agricultural deities, Pomona is not associated with the harvest itself, but with the flourishing of fruit trees. She is usually portrayed bearing a cornucopia or a tray of blossoming fruit. In some areas, her festival was observed later in the harvest season, around November 1.
Vulcan was associated with the destructive powers of fire, so his celebration fell each year during the heat of the summer months, when everything was dry and parched, and at higher risk of burning. After all, if you were worried about your grain stores catching fire in the August heat, how better to prevent this than to throw a big festival honoring the fire god?