Twenty two days of dating
Although, as explained in the article GENERAL CHRONOLOGY, the monk known as Dionysius Exiguus, when resident in Rome, c.
Generally speaking (though the rule admitted of many exceptions, especially later) the regnal year was calculated from the day of coronation or consecration.As a rule the charters emanating from the chancery of the Western Emperors are much more liable to this form of error than those of the Holy See (Bresslau, ib., 844). In any case it remains certain and is admitted by all serious writers upon diplomatics that the mere fact that an erroneous date occurs in a document, especially when we are dealing with the earlier Middle Ages, cannot by itself be accepted as a proof, or even a presumption, of the spuriousness of the document.But even the bulls of such a pontiff as Innocent III are not unfrequently at fault, and as Léopold Delisle has shown, an erroneous calculation of the indiction may be perpetuated through a whole series of authentic documents (Bib. The point of main interest in this connection is to determine the source and period of the introduction of our present system of dating by the Christian Era.The indiction was a cycle of fifteen years, the first of these cycles being conceived to have started at a point three years before the beginning of the present Christian Era.It was usual to indicate only the position of the year in the current indiction, and no notice was taken of the number of cycles already completed.What is more, we may notice the striking fact that the regular employment of the Christian Era in English charters began just at the period of Bede's pre-eminent influence.
It is only from about the year 679 that we are able to appeal to English charters of indisputable authenticity.
In the official acts of most of the countries of Christendom, and notably in England, the regnal year of the sovereign was always given and sometimes this was the only indication of the year.
As a continuous system of year enumeration the oldest era in practical use appears to have been that known as the "Era of the Martyrs" or "of Diocletian" () was in familiar use in Spain from the fifth century down to late in the Middle Ages.
The principle that imperial decrees and charters must be "dated" as a condition of validity, i.e.
that they must bear upon them the indication of the day and year when they were delivered, may be traced back to the time of Constantine.
On the other hand, the last three agree in using the Christian Era and from this time the practice is continuous.