Parilia April 21

In the late Republic, the Parilia became associated with Rome's birthday. Many accounts of the founding of Rome exist, but the particular one related to the Parilia is described by Ovid in his Fasti. According to this myth, Romulus, arriving in Rome on the day of Parilia, took a stick and carved a line in the ground which defined the boundaries of the new city (pomerium). He then prayed to the gods Jupiter, Mars and Vesta for protection of this area. However, his brother Remus, unaware of the limits, crossed the line and was knocked down by Romulus' henchman Celer.

The pastoral structure of the festival is provided by the shepherd himself. After the sheep pen was decorated with green branches and a wreath was draped over the door, the rest of the ceremony proceeded in order. At the first sign of daylight, the shepherd would purify the sheep: by sweeping the enclosure and then building a bonfire of straw, olive branches, laurel and sulfur. The noises produced by this burning combination were interpreted as a beneficial omen. The shepherd jumped through this flame, dragging his sheep with him. 

Offerings of millet, cakes and milk were then presented before Pales, marking the second segment of the ceremony. After these offerings, the shepherd wet his hands with dew, faced east and repeated a prayer four times. Such prayers requested Pales' help in freeing the shepherd and flock from harm caused by accidental wrongdoing (e.g., trespassing on sacred lands and taking water from a sacred water source). The final part of the rural celebration used the drink burranica, a combination of milk and sapa (boiled wine). After consuming this beverage, the shepherd jumped through the fire three times, ending the ceremony.

The urban form of Parilia, on the other hand, is mixed with other Roman religious practices and practiced by a priest. Ovide personally participated in this form and described his experiences in the Fasti. While the central actions of the rural ceremony continue, the urban form adds two ingredients from other religious festivals: the Fordicidia and the October Horse. The Fordicidia sacrifices a pregnant cow to the deity Tellus to promote the fertility of livestock and fields. 

The unborn calf is then removed from the uterus and burned. The October Horse is the right-hand man of the team that won a particular chariot race on October 15 of the previous year. Together, the ashes of the unborn calf and the blood from the head of the October horse are mixed by the Vestal Virgins and added to the burning bean straw of the bonfire. Dumézil questioned whether Equus October provided horse blood, since the two ancient sources that mention the ingredient fail to identify the victim.