Parilia

The Parilia or Palilia was an ancient Roman festival of rural character performed annually on 21 April, aimed at cleansing both sheep and shepherd.

[1] Ovid describes the Parilia at length in the Fasti, an elegiac poem on the Roman religious calendar, and implies that it predates the founding of Rome (753 BC in the Varronian chronology), as indicated by its pastoral and preagricultural concerns.

According to this myth, Romulus, upon reaching Rome on the day of the Parilia, took a stick and engraved a line in the ground that defined the boundaries of the new city (pomerium).

Caligula instituted into the celebration a procession of priests, noblemen, boys and girls of noble birth singing of his virtues while escorting the Golden Shield, previously bestowed upon him by the citizens of Rome, to the Capitol.

At the first sign of daylight, the shepherd would purify the sheep: by sweeping the pen and then constructing a bonfire of straw, olive branches, laurel, and sulfur.

[3] While the central actions of the rural ceremony carry over, the urban form adds two ingredients from other religious festivals: the Fordicidia and the October Horse.

[4] Dumézil questioned whether the Equus October provided the horse blood,[7] since the two ancient sources that mention the ingredient omit identifying the victim.