The Roman Calendar: Hours, Days, Nundinae, Kalends, Nones and Ides
While the modern world has adopted the universal system of a day of twenty-four equal hours, the seven-day week, with roughly four weeks fitted into each of the twelve months, the Romans structured their days and months quite differently.
This article outlines the structure of the Roman month, starting with the day and its hours and going on to describe the other important calendrical markers: the Nundinae, the Kalends, the Nones and the Ides and the days Fasti and Nefasti.
The Roman Day: the Horae
The Roman day was divided into twelve equal hours (horae) counted from sunrise to sunset. The first hour after sunrise would be designated the First Hour and the second would be the Second Hour and so on. The last hour of the day would always be the twelfth hour. The hours themselves varied in length, depending on the time of the year, being shorter in the winter and longer in the summer in order to fit them into this twelve hour pattern.
Around the time of the Summer Solstice, Roman hours would be approximately an hour and a quarter of our Equinoctial hours. The First Hour would begin at about four thirty am by our reckoning and the Twelfth Hour would end just after seven thirty pm. At the time of the Winter Solstice, hours would last around forty five minutes by our reckoning. The First hour would begin at about seven thirty and the final hour of the day would be around four thirty pm.
The Romans further divided the day into morning (manes) noon (meridies) and afternoon (pomeridianum).
Roman Clocks: Gnomon and Clepsydra
Clockwork was not invented until around the twelfth century CE. The Romans used other forms of technology for telling the time. The two basic means used by the Romans were the sundial or gnomon and the water-clock or clepsydra. The clepsydra worked by allowing water to pour through one glass vessel through a narrow opening to one underneath it, with the vessel marked off into twelve equal sections corresponding to the hours. Roman horologia (timepieces) ranged from simple household articles to ornate and elaborate devices that might be on display in public places such as outside temples and courts, or in the homes of the wealthy. The very well off also kept slaves with the specific task of announcing the time to the household.
While we have a seven day week structured around the Christian Sabbath, influenced by the Jewish Shabbat, the Romans had a nine day cycle based around the Nundinae or Market Day.
Beginning on the first of January, the days of the year were divided into blocks of eight, marked A – H on Roman calendars. The eighth day was the Nundinae, Market Day when people came into the city to buy and sell and transact business. The Romans reckoned this as a cycle of nine days because they counted from Nundinae to Nundinae. It was a day particularly associated with the plebeians, the ordinary people of Rome.
The Kalends, Nones and Ides
The Roman month was further divided up and reckoned by the Kalends, the Nones and the Ides.
The Kalends marked the first day of each month, and gave the word Calendar its name.
The Nones occurred on the seventh of March, May, July (or Quinctilis as it was called before the month was renamed in honour of Julius Caesar) and October and on the fifth of the other months.
The Ides always fall eight days after the Nones. Thus the famous Ides of March on which Julius Caesar was assassinated fell on the 15th of March.
The Romans numbered the days of the month by counting up towards the nearest Kalends, Nones or Ides. If, for example, you wanted to make an arrangement for the 23rd of January, you would state the intended date as the tenth day before the Kalends of February.
Days Fasti and Nefasti
Romans further divided their days into those on which courts could be held and business transacted, and those on which such public business was forbidden. Days on which these activities could take place were Fasti and were marked with an F on the Calendar. Days could also be partly Fasti and partly Nefasti so that only part of the day could be devoted to legal or business transactions. Nefasti days were often religious festivals dedicated to the Gods. On many such days, everyone, including slaves would be exempt from working.