Roman calendar in the context of "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. It was carried out in acknowledgment to the Roman deity Pales, a deity of uncertain gender who was a patron of shepherds and sheep.

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. During the Republic, farming was idealized and central to Roman identity, so the festival took on a more generally rural character. Increasing urbanization caused the rustic Parilia to be reinterpreted rather than abandoned, as Rome was an intensely traditional society. During the Imperial period, the date was celebrated as the birthday of Rome (Latin: dies natalis Romae or natalis Urbis).

Year 404 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Tribunate of Volusus, Cossus, Fidenas, Ambustus, Maluginensis and Rutilus (or, less frequently, year 350 Ab urbe condita). The denomination 404 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Year 403 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Tribunate of Mamercinus, Varus, Potitus, Iullus, Crassus and Fusus (or, less frequently, year 351 Ab urbe condita). The denomination 403 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year (without exception). The Julian calendar is still used as a religious calendar in parts of the Eastern Orthodox Church and in parts of Oriental Orthodoxy as well as by the Amazigh people (also known as the Berbers). For a quick calculation, between 1901 and 2099 the much more common Gregorian date equals the Julian date plus 13 days.

The Julian calendar was proposed in 46 BC by (and takes its name from) Julius Caesar, as a reform of the earlier Roman calendar, which was largely a lunisolar one. It took effect on 1 January 45 BC, by his edict. Caesar's calendar became the predominant calendar in the Roman Empire and subsequently most of the Western world for more than 1,600 years, until 1582 when Pope Gregory XIII promulgated a revised calendar. Ancient Romans typically designated years by the names of ruling consuls; the Anno Domini system of numbering years was not devised until 525, and became widespread in Europe in the eighth century.

Numa Pompilius (Classical Latin: [ˈnʊma pɔmˈpɪliʊs]; c. 753–672 BC; reigned 715–672 BC) was the legendary second king of Rome, succeeding Romulus after a one-year interregnum. He was of Sabine origin, and many of Rome's most important religious and political institutions are attributed to him, such as the Roman calendar, Vestal Virgins, the cult of Mars, the cult of Jupiter, the cult of Romulus, and the office of pontifex maximus.

Festivals in ancient Rome were a very important part of Roman religious life during both the Republican and Imperial eras, and one of the primary features of the Roman calendar. Feriae ("holidays" in the sense of "holy days"; singular also feriae or dies ferialis) were either public (publicae) or private (privatae). State holidays were celebrated by the Roman people and received public funding. Games (ludi), such as the Ludi Apollinares, were not technically feriae, but the days on which they were celebrated were dies festi, holidays in the modern sense of days off work. Although feriae were paid for by the state, ludi were often funded by wealthy individuals. Feriae privatae were holidays celebrated in honor of private individuals or by families. This article deals only with public holidays, including rites celebrated by the state priests of Rome at temples, as well as celebrations by neighborhoods, families, and friends held simultaneously throughout Rome.

The Fasti (Latin: Fāstī [ˈfaːstiː], "the Calendar"), sometimes translated as The Book of Days or On the Roman Calendar, is a six-book Latin poem written by the Roman poet Ovid and made public in AD 8. Ovid is believed to have left the Fasti incomplete when he was exiled to Tomis by the emperor Augustus in 8 AD. Written in elegiac couplets and drawing on conventions of Greek and Latin didactic poetry, the Fasti is structured as a series of eye-witness reports and interviews by the first-person vates ("poet-prophet" or "bard") with Roman deities, who explain the origins of Roman holidays and associated customs—often with multiple aetiologies. The poem is a significant, and in some cases unique, source of fact in studies of religion in ancient Rome; and the influential anthropologist and ritualist J.G. Frazer translated and annotated the work for the Loeb Classical Library series. Each book covers one month, January through June, of the Roman calendar, and was written several years after Julius Caesar replaced the old system of Roman time-keeping with what would come to be known as the Julian calendar.

The popularity and reputation of the Fasti has fluctuated more than that of any of Ovid's other works. The poem was widely read in the 15th–18th centuries, and influenced a number of mythological paintings in the tradition of Western art. However, as scholar Carole E. Newlands has observed, throughout the 20th century "anthropologists and students of Roman religion … found it full of errors, an inadequate and unreliable source for Roman cultic practice and belief. Literary critics have generally regarded the Fasti as an artistic failure." In the late 1980s, however, the poem enjoyed a revival of scholarly interest and a subsequent reappraisal; it is now regarded as one of Ovid's major works, and has been published in several new English translations. Ovid was exiled from Rome for his subversive treatment of Augustus, yet the Fasti continues this treatment—which has led to the emergence of an argument in academia for treating the Fasti as a politically weighted work.

Martius or mensis Martius ("March") was the first month of the ancient Roman year until possibly as late as 153 BC. After that time, it was the third month, following Februarius (February) and preceding Aprilis (April). Martius was one of the few Roman months named for a deity, Mars, who was regarded as an ancestor of the Roman people through his sons Romulus and Remus.

March marked a return to the active life of farming, military campaigning, and sailing. It was densely packed with religious observances dating from the earliest period of Roman history. Because of its original position as the first month, a number of festivals originally associated with the new year occurred in March. In the Imperial period, March was also a time for public celebration of syncretic or international deities whose cultus was spread throughout the empire, including Isis and Cybele.

A month is a unit of time, used with calendars, that is approximately as long as a natural phase cycle of the Moon; the words month and Moon are cognates. The traditional concept of months arose with the cycle of Moon phases; such lunar months ("lunations") are synodic months and last approximately 29.53 days, making for roughly 12.37 such months in one Earth year. From excavated tally sticks, researchers have deduced that people counted days in relation to the Moon's phases as early as the Paleolithic age. Synodic months, based on the Moon's orbital period with respect to the Earth–Sun line, are still the basis of many calendars today and are used to divide the year.

Calendars that developed from the Roman calendar system, such as the internationally used Gregorian calendar, divide the year into 12 months, each of which lasts between 28 and 31 days. The names of the months were Anglicized from various Latin names and events important to Rome, except for the months 9–12, which are named after the Latin numerals 7–10 (septem, octo, novem, and decem) because they were originally the seventh through tenth months in the Roman calendar. In the modern Gregorian calendar, the only month with a variable number of days is the second month, February, which has 29 days during a leap year and 28 days otherwise.