Various proposals have been, and continue to be, made for dating the Voynich Manuscript itself and the writing (there being some debate as to whether the text was written in the period in which the vellum was prepared or later), partly linked to who was considered to be the author or authors (there have been a range of suggestions including the Cathars, Roger Bacon, Leonardo da Vinci and Wilfrid Voynich himself).
However in February 2011 it was announced that the manuscript, and the writing thereon had been scientifically dated to the early 15th century which eliminates a number of the suggested authors from earlier periods. It would, however, be possible for the manuscript to make use of, or copy earlier documents and other information.
This was the period when printing was just being developed in Europe, and significant religious and other changes were occurring - including the Ottoman takeover of Constantinople/Istanbul, and explorations of the wider world.
It has been argued that the text was written some time after the vellum of the manuscript had been prepared. While certain artists' and similar materials can be kept unused in some workshops for long periods of time, there is probably a practical limit for vellum.
From the Wikipedia page on the VM :
In 2009, University of Arizona researchers performed C14 dating on the manuscript's vellum. The result of that test put the date the manuscript was made between 1404 and 1438. In addition, the McCrone Research Institute in Chicago (Wikipedia page ) found that the paints in the manuscript were of materials to be expected from that period of European history. It has also been suggested that the McCrone Research Institute found that much of the ink was added not long after the creation of the parchment, but the official report contains no statement to this effect.
More information can be found here .
Another article is here