If you’re really so petty I’m a bit reluctant to answer your question; who knows what kind of reply I might get? For the sake of grounding the question a bit better, I’m going to say that you’re the lord of South Cadbury in Somerset, because South Cadbury is a well-excavated site that can definitely be said to have had an elite presence at the time you’re asking about. To be fair, the lord of South Cadbury may not have been all that petty, in fact they may have been the ruler of Dumnonia, but it’s useful to have an actual site and artefactual assemblage to ground this.

Often people ask this sort of question and someone is able to simply respond, 'Yes, this is what calendar these people used and this is how they dated years.' In terms of the calendar, the answer in this case is, indeed, fairly simple: the Julian calendar was well-established in Britain over three and a half centuries of Roman rule (by facile comparison, Britain has only had the Gregorian Calendar for two and a half centuries). As for how the years were counted: that is rather less clear. We have a single documentary source from sixth-century Britain: the De Excidio Britanniae of Gildas, and this includes no annual dates. We also have two sources written by a Briton of the fifth century, Patrick, but these also include no annual dates. There are many stone inscriptions from the period, but they do not have dates either.

People did, nonetheless, keep track of the years. The Irish annals record a 'failure of bread' in 536, the year of the volcanic ash cloud and thus probably meaning that the annal is accurate. This is despite the hypothetical shared source for these annals being unlikely to have been begun until decades after this event. These annals list every year even if there are no entries for that year, suggesting that the hypothesised original ‘Chronicle of Ireland’ kept track of the passing years by marking every year, writing the ‘Kalends of January’. This suggests that the chroniclers lacked numbered annual dates in the sources they drew upon, and instead kept track of the years by literally counting them. This counting, however, must have been reasonably accurate, hence why monks decades later were able to accurately place the failure of bread in 536. Likewise, Gildas appears to tell us that 44 years have passed since the siege of Mount Badon, which was also the year of his birth. I say ‘appears to’ because the wording is not completely clear and Bede, who admittedly had access to an earlier manuscript than we do, believed that Gildas meant that the battle of Badon took place 44 years after the arrival of the Saxons in Britain. Modern historians have made alternative suggestions, such as that Gildas meant the battle took place 44 years after Ambrosius’s first victory against the Saxons, or, in the case of Daniel McCarthy and Dáibhí Ó Cróinín, that he meant 44 years into the 84 year Insular Easter cycle. The nature of this cycle was only confirmed in 1985 when Ó Cróinín discovered the Easter table, replicated in a tenth-century Italian manuscript. Whatever its relevance to the passage in De Excidio, the use of this Easter cycle informs us that the Cambro-Irish church did indeed keep careful count of the years. It does, however, seem unlikely that the aristocracy or peasantry would have conceived of the years according to this mathematical method of ensuring Easter fell upon the correct day. It is therefore worth considering what other methods of dating might have been used.

In the Roman Empire regnal years were now the usual method of dating. The ancient method of dating a year by naming its two consuls was on the way out and would be rendered impossible in 541, when the emperor Justinian made the consulship just another title attached to the emperor. The ninth-century Welsh source, the Historia Brittonum uses consular dates for supposed fifth-century events, but these may well have been derived from Roman sources, rather than being recorded in Britain throughout the fifth-century. In Gaul, the historian Gregory of Tours used regnal years to date events, but, in this case, the regnal years of the Frankish kings. Whether the Franks themselves used this as an established dating system at this time is unclear, but Gregory’s regular use of regnal years suggests that someone, Frankish or Roman, was keeping careful count of how long the king had reigned. The English historian Bede, writing in the early eighth century, uses regnal dates for early seventh-century rulers, although it is possible that this practice was introduced by or as a consequence of the Augustinian mission. It may well have been that the Britons also used regnal years to date matters, but then the question is whose regnal years? Britain in this period does seem to have had rulers with wide-ranging influence, such as Riothamus and Maglocunnus, but polities appear to have typically been small; Gildas attests to Dumnonia, the Vita Sancti Samsonis attests to Gwent (at this point including Glywysing), and both attest to Dyfed. Given Gildas’s disdain for contemporary rulers, it would make sense that he would avoid using regnal years even if others did. The ninth-century Historia Brittonum does use regnal years, and for a king of Gwynedd (someone ruling a kingdom of the sort of size which might been seen in the sixth century). However, we must remember that we are talking about a difference of three hundred years. The Historia also mentions regnal years for the semi-legendary fifth-century ruler Vortigern, but the Historia’s material on the fifth century is not regarded as reliable.

So, returning to your question, if you, a Romano-British lord in sixth-century Somerset, were asked what year it is, your reaction might well be confusion, though not the sort of confusion you’d express if asked what the year is these days. On the other hand, if you were connected to the Eastern Mediterranean by trade, as the ruler of South Cadbury was, you might actually have been told how long Justin had reigned by a Greek merchant, or by an aristocrat or cleric who had met a Greek merchant. Likewise, you might well have had news from Gaul, probably via Brittany, about the Frankish kings. So if you were asked by a wealthy visitor from the Continent, you might show off your knowledge of world affairs by telling them that it is the third year of the reign of Justin, or the tenth year of the reign of Childebert. But in all likelihood you wouldn’t conceive of events in your own life according to these foreign regnal years. Even educated people such as Gildas don’t appear to have used these dates to measure British events. The use of native regnal dates meanwhile is entirely possible; British rulers had taken on the royal trappings of Roman emperors, so why might they not also take on the practice of dating by regnal years. Gildas mentions kings being anointed, which David Petts has noted appears to be drawn from practices used in the Bible, so it hardly seems unreasonable to suggest that the Britons might have also adopted the Biblical practice of using regnal dates. This is, nevertheless, speculation, and we shouldn’t let it draw from the fact that numbered dates are completely absent from the writings of Patrick and (conventionally) Gildas. It would therefore appear that numbered dates factored far less into people’s conceptions of time than they would do several centuries later. This does not mean, however, that their sense of the passage of time was thoroughly vague. Gildas and the Irish chroniclers indicate that people kept track of the years reasonably well. It must be noted, however, that people may well have had a far less clear conception of events long before their own lifetimes. Badon Hill is the only precise year Gildas gives us; his sense of earlier events appears to be much vaguer. The Irish annalists meanwhile scrupulously record three supposed dates for the death of Patrick, well aware that only one could be true. So, to be frank, the answer is we really don’t know what you, a Romano-British lord in 521, would say if asked what year it is. You might state the year of your own rule, or the year of the rule of a greater king, perhaps even that of the Roman emperor. You might direct the inquirer to a learned cleric, who could tell you where we were are in the Easter cycle, or how long it has been since a significant event. Or you might simply be confused by the idea of labelling the years in such a way, especially the current year.

Primary Sources

Annales Cambriae

The Annals of Ulster

Bede, Historia Ecclesiastica Gentis Anglorum

Gildas, De Excidio Britanniae

Gregory of Tours, Historia Francorum

Historia Brittonum

Patrick, Confessio

Patrick, Epistola

Procopius, History of the Wars

Vita Sancti Samsonis

2 Kings

Secondary Sources

Lesley Alcock, By South Cadbury is that Camelot

David Dumville, ‘The Chronology of De Excidio Britanniae, Book 1’

Michael Hanaghan, ‘Narrative Time and the Letters of Sidonius Apollinaris’

Daniel McCarthy and Dáibhí Ó Cróinín, ‘The ‘Lost’ Irish 84-Year Easter Table Rediscovered’

Daniel McCarthy, ‘The Chronology and Sources of the Early Irish Annals’

Thomas D. O’Sullivan, The De Excidio of Gildas: Its Authenticity and Date

David Petts, ‘Christianity and the End of Roman Britain’