Dating a medieval documents can be rather complicated, and this is partly because medieval dates are so comprehensive. Multiple dates were supposed to remove any difficulties and uncertainties, but often they only succeeded in confusing the issue, and they frequently clash. The date is always the last part of a document, sometimes before, but usually after the signature. Its most important part is the year. This is usually rather straightforward, especially in late period texts, even though it is usually expressed in rather florid prose. Given in the thirteen hundredth year and the fiftieth and sixth year after the birth of our Lord and Saviour Jesus Christ, is one of the more concise statements of a year. Sometimes the years are also counted in a more personal way (this can be an oblique political statement, but usually it merely reflects a local or regional custom); the dates of reference can be the creation of the world (4004 BC), the foundation of Rome (753 BC), or the beginning of the reign of the current pope, emperor, king, bishop etc. Imperial documents confuse the issue even further by the use of ecclesiastical, imperial and royal reckonings: Given in the year 1356, in the eleventh year of our kingship and the third year of the Empire. This basically means that the Emperor in question was crowned in Rome eight years after his proclamation as German king - unless the scribe managed to mix up the dates which happened quite frequently. Another problem is when to place the beginning of the year. For most scribes (at least those working in a secular chancery) the year begins on 1 January, but there are some who start the new year with the first Sunday of Advent or Easter. A lot of the documents also preserve an older tradition, and include the current indiction (Roman tax-period). An indiction lasts approximately a year and fifteen indictions make up a tax-cycle. As there weren't any direct taxes in the Middle Ages, the inclusion of indictions was rather pointless, and the scribes usually got them wrong. Normally indictions can safely be ignored. When indictions are used, the Roman reckoning of days is often included, too (that is Calends, Ides etc.). Months aren't much of a problem; they are usually not even mentioned in the documents. But the description of days makes more than up for that. The normal thing to do is to use the day of a saint. There are at least ten saints to be commemorated on every single day of the year, however, and some scribes seem to have delighted in choosing the most obscure ones available. Those saints were often venerated only locally, and many of them were never officially canonised, and they are thus missing from the official calendar. Even though the number of saints available on any given day should have been enough of a choice for anyone, there were times when none of them met with the approval of the chancery. In that case the scribes (or chancellor, depending on how important the document was) started hunting for more acceptable saints on the days immediately preceding or following the issuing of the document. Great pains were also taken to always include favourite saints or saints appropriate to the subject matter of the document, and this when you get dates like three nights before the Immaculate Conception or two days after the Feast of St. George. And that is usually the end of the date and the document, even though the list of witnesses and the signature sometimes follow after the date. And to show what the date of an official imperial document really looked like, here is an example from a proclamation against the formation of Leagues of Towns by Frederick II (which unfortunately doesn't list the day): Acta sunt hec anno dominice incarnationis millesimo duocentesimo tricesimo secundo, mense Aprelis quinte indiccionis, imperante domino nostro FR secundo Dei gratia invictissimo Romanorum imperatore, Ierusalem et Sicily reggae, anno Romania impair IOUs duodecimo, regain Ierusalem septum, regain veer Sicily tricesimo quarto. [Given in the year 1232 after the Incarnation, in the month of April of the fifth indiction, in the reign of our Lord Frederick II, by God's grace invincible Emperor of the Romans, king of Jerusalem and Sicily, in the twentieth year of his Empire, the seventh year of the kingdom of Jerusalem, but the 34th year of the kingdom of Sicily] There is only one comprehensive survey of the dating of medieval documents, complete with lists of saints and timetables (showing indictions, Byzantine and Jewish calendars etc.), and that is Grotefends Handbuch der Zeitrechnung des Mittelalters und der Neuzeit. It is unfortunately written in German, but the lists and timetables might be useful anyway.