In 45 BCE, Gaius Julius Caesar introduced the so-called Julian calendar based on the work of the Egyptian Sosigenes. A few inaccuracies had occurred in his calculation, but they hardly mattered at first. This changed after the Council of Nicaea in 325 decided to introduce a standard Easter date for Christianity (the first Sunday after the spring full moon), which was also to be calculated in advance. Already in the early Middle Ages, it was recognised that the excess length of the calendar was growing, while the calculated beginning of spring was slipping further and further towards the beginning of the year. All attempts by the church to renew the calendar failed. Only the calendar commission set up by Pope Gregory XIII came to a result. Using the Compendium novae rationis restituendi Calendarium by Luigi Lilio, the Jesuit and astronomer Christoph Klau presented a comprehensive calendar reform. On 24 February 1582, the Pope issued the bull Inter gravissimas, which ordered the introduction of the new, so-called Gregorian calendar. This included several innovations, the most striking of which was the deletion of 10 days. Thursday 4 October 1582 (Julian date) was followed by Friday 15 October 1582 (Gregorian date).
Unfortunately, the efforts of the Papal Calendar Commission were only granted modest success for the time being. In times of Reformation, Counter-Reformation and religious wars, the whole of Europe was by no means prepared to accept a reform of the head of the Catholic Church, no matter how useful it might be. To make matters worse, they had forgotten to draw attention to the scientific aspect of the amendment. At first, Spain, Portugal, large parts of Italy and some parts of Poland adopted the calendar. If not in October, at least in the same year, France and Catholic Germany followed – where some areas only gradually became familiar with it. It took until the first decades of the 20th century for the Gregorian calendar to become established worldwide.
To convert a date from the Julian – also called the old – style to the Gregorian – or new – style, a certain number of days must be added to the respective date.
Up to and excluding | 1 March 1700 | one needs | 10 | days to add. |
1 March 1800 | 11 | |||
1 March 1900 | 12 |
The change from the Julian to the Gregorian calendar only partially complicates the dating of certain events. For even before the calendar reform, there had been complete disagreement regarding a day that is of utmost importance for the calendar of an entire year. In the Middle Ages, there were six different beginnings of the year, some of which have survived well into modern times.
Name | Date | used in |
---|---|---|
Circumcision style | 1 January | Münster, Poland |
Pre-Caesarian beginning of the year | 1 March | Venice |
Annunciation style (Marian year) | 26 March | Trier, Metz, Aquitaine, Auvergne, Angoumois, Limousin, Reims, Delft, Lorraine, England, Florence, Siena, Romanesque part of Lausanne |
Easter | Good Friday or Holy Saturday | France, Burgundy, Flanders, Brabant, Hainaut, Zeeland, Cambrai, Touraine, Holland, Toul, Verdun |
Byzantine beginning of the year | 1 September | Bari, Amalfi, Naples, Gatea, Puglia, Calabria, Russia |
Christmas | 25 December | German Empire, Mainz, Bremen, Magdeburg, Gniezno, Kammin, Salzburg, Prague, Hungary, Minden, Cologne, Osnarbrück, Utrecht, Liège, Dauphiné, Guelders, Friesland, England (until the beginning of the 11th century), Milan, Genoa, Lucca, Padua, Estonia, Livonia, Basel, Constance, Chur, German part of Lausanne, Geneva, Lucerne |
So what does this mean for Christopher Marlowe? He lived and worked in a country that followed the Julian calendar until 1752 and set the beginning of the year on 25 March. If the necessary conversion tables are available, this is no problem. The difficulty lies not in the conversion, but in its omission. Hardly any work indicates which calendar or date style is used. Unless otherwise noted, all dates here correspond to the Gregorian calendar with a start of the year on 1 January.