By Peter Carney - Volunteer Guide

The emperor Hadrian was born in what is now Southern Spain on the 24th of January 76 AD.  However, this is not how Hadrian himself or anyone else in the Empire would’ve referred to this date. To them, it was the ninth day before the Kalends of February in the year of the consuls Titus and Vespasianus or 829 AUC. This last refers to Ab Urbe Condita which is the date of the founding of Rome by Romulus and the Romans knew this as the 11th day before the Kalends of May year 1 or for us the 21st of April 753 BC.

The Kalends, Nones and Ides are the way Romans broke up the month. So the Kalends refers to the New Moon at the beginning of every month. The Nones are 7 days later referring to the first quarter and the Ides refer to the Full Moon around the middle of every month. It doesn’t always work with the moon of course, but the names remained anyway, and Romans would have calculated the date as so many days before the Nones, Ides or Kalends, hence Hadrian’s birthday is 9 days before the Kalends of February and Caesar was famously assassinated on the Ides of March, in this case meaning the 15th of March.

This system of working out the dates within a year had only been in use since the time of Julius Caesar. Before that, during the Roman Republic, the year had 10 months and 304 days. This was clearly chaotic and around 60 or so days were added during the winter so that spring occurred in March. The pontifices or priests were in control of this led by the Pontifex Maximus. However the number of days added were indeterminate so if the Pontifex Maximus approved of the Consuls for that year he could add a few extra days making the year longer, and vice versa if not. When Julius Caesar became the Pontifex Maximus for the year we would call 46 BC he reformed the whole system. It was realised that the actual length of the year was not just 365 days but 365 and a quarter days. Caesar reorganised the year into 12 months, added an extra day every 4 years and the Julian calendar was born.

In the museum at Vindolanda is a very rare part of a Roman calendrical clepsydra. This broken fragment only has the month of September on it but is marked with the Kalends (K), Nones (N) and Ides (I) marked as well as the autumnal equinox (AE). It has holes for a peg to move along every two days. Dr Alexander Mayer argues that it is probably the rim of a bowl that contained water and markings down the inside measuring hours of the day called a clepsydra. The water drains out through a small hole at an exact rate so giving the time while the rim gives the date.  Such a device is similar to one mentioned by Marcus Vitruvius Pollio in his ‘De Architectura’. It would’ve been relatively inaccurate by today’s standards and Seneca remarks in the first century that even ‘philosophers agree more often than clocks’. However no more than 2 or 3 have been found in the entire empire and it is a complex piece of technology to turn up in a fort on the far North Western Frontier.

Other calendars existed giving more accurate dates for religious and military purposes called Fasti. Anniversaries were as important to people then as they are to us today. In fact, if anything more important then. Not only your own but birthdays of friends, relatives and patrons were celebrated as well. The expense of gifts given and amounts of food and drink consumed at the party tended to be determined by the social class and wealth of those involved but almost always needed several glasses of ‘good cheer’ and the ubiquitous cake. An occasion would be organised and invitations sent as shown by Claudia’s letter to her friend Lepidina in one of Vindolanda’s famous writing tablets. Even in the relatively trying circumstances of the frontier, a social life was as important then as a social life now.

The poet Martial writes in one of his epigrams:

‘ I love your April birthday as much as my own in March – and so I should ……….. The one gave me life but the other gave me a friend.’

And Marcus Aurelius writes to his friend Fronto:

‘ I love you just as I love my own self, and on this birthday of yours I want to offer prayers on my own behalf.’

A birthday would be a religious occasion too since religion in the Roman world could not be divorced from any other aspect of life. So along with gifts and feasting, prayers would be said with flowers and incense on the altar, often dedicated to the genius of the person concerned. This could go further with the celebrant dressed in white, garlanded with flowers and anointed with oil.  

Roman life for many involved patronage and practically everyone was a patron of somebody and a client of someone else. So celebrating the birthday of your patron was important politically and carefully observed. This went all the way up to the Emperor whose birthdays were celebrated universally. In a world with no notion of the ‘week-end’ these occasions were, along with ‘holy days,’  eagerly looked forward to and enjoyed.

Emperors took advantage of these anniversaries, along with any others they could shoehorn in, to provide games and circuses for their people. On the occasion of his 43rd natales Hadrian, who’d been emperor for about a year and a half by then, ordered celebrations empire wide and in Rome organized games in the Colosseum that not only slaughtered gladiators but hundreds of lions. Exotic creatures that must’ve been difficult and expensive to acquire.  Anniversaries of all kinds were celebrated in this way including the birthdays of long dead emperors along with the foundation dates of temples, cults, legions and even cities.

One of the most spectacular was by the emperor known to us as Philip the Arab who in 248 AD celebrated the 1000th year of the founding of Rome. The city was bedecked with banners and flowers. There were days of theatrical performances, banquets, contests, and copious amounts of food and wine. In all the circuses, especially the Circus Maximus, as well as the Colosseum, there were endless chariot races, the slaughter of hundreds of exotic animals and 2000 gladiators. People queued all night.

This celebration of emperors birthdays, alive or dead, added to the ‘emperor cult’ across the Empire and with the undivorceable religious aspect added to the emperors divinity cult as well. Given that they were mostly drunken holidays actual belief didn’t really matter. Nowadays only one divinity in the Christian world has their birthday celebrated every year as Christmas replaced the Roman festival of Saturnalia.

Anyway today’s the day to raise a glass to Hadrian, felix sit natales dies.

This blog has been written as part of our Roman Holiday Project.


Konstantin Bikos and Vigdis Hocken – The Roman Calendar

Kathryn Argetsinger – Birthday rituals – Friends and Patrons in Roman Poetry and Cult

Frank Holt – The Roman Millenium

Alexander Mayer – The Vindolanda Calendrical Clepsydra: Time Keeping and Healing Waters