When Wilfrid Voynich first saw the manuscript, he immediately considered the 13th Century Franciscan friar Roger Bacon as its possible author. He then embarked on a thorough study of the MS's history, in the hope of being able to prove this. While that would make the Voynich MS an incredibly important and valuable document in the history of science, a fact to which an antiquarian book dealer would not have been insensitive, it is apparent from the way in which he perfomed his search that he seems to have genuinely believed that Bacon was the writer of the Voynich MS.
The Marci letter indicates that the MS was bought by the Holy Roman Emperor Rudolf II of Bohemia (who ruled until 1611), for the sum of 600 ducats. The source for this information is Dr. Raphael Missowski, who was teacher of the young Ferdinand III and later royal procuror at the court. He died in 1644, so this piece of oral information was 22 years old when Marci wrote his letter. Dr.Raphael also reports that he thought that the VMs was written by Roger Bacon, i.e. in the 13th Century.
There exists, however, no specific confirmation of the identity of the 'bearer' of the MS. Voynich indicated that according to him the most likely candidate was John Dee, but he had set out to prove that the MS originated with Roger Bacon, so he had been specifically looking for such a link. Since the Bacon origin is no longer considered likely, the connection with Dee (and his associate Kelly) have very little ground. Rudolf II of Habsburg ruled from 1576 to 1611 and there is no indication at which point in this 35-year span the sale took place.
Many solutions to the Voynich MS have been suggested in the past, and they all come with a proposed time and place of origin. Since none of these solutions has been generally accepted, the associated hypotheses of the origin cannot be confirmed. Additionally, analyses of the illustrations, the script and the text statistics have led to suggestions for the origin of the Voynich MS. In the following, they are summarised together.
While the reader is of course allowed to make up his own mind about the various proposals listed above, the general feeling is that a date of origin between 1450 and the early years of the 16th Century, and a place of origin in Italy or Central Europe are most likely to be correct. There is a long list of visitors to Rudolf's court who could have potentially brought the MS to Prague. Finding the right one could help in further narrowing down the origin of the Voynich MS.