This is just a quick post to share a project that’s going on at the Voynich ninja forum. Since this is a work in progress, this post can serve as a quick way to see its current status.

It is surprisingly difficult to say something about the origin of the VM with absolute certainty, but luckily there are a handful of clear cultural indicators. One example is the clothing style worn by the Zodiac figures, which was the fashion from c. 1400 -1430, overlapping nicely with the carbon-dating of the vellum to 1404–1438.

Another such indicator is the presence of swallowtail merlons on the Rosettes foldout. These are also known as Ghibelline merlons, since they were a symbol of this political faction in Italy in the 12th-14th centuries. (It seems that throughout the 15th century, swallowtail merlons lost most of their political meaning and became purely decorative). Because of this cultural context, battlements with this shape are typical of certain regions. Since “northern Italy” is a bit vague, I wanted to get a better image of these regions.

However, there are some difficulties. It is important to keep in mind what exactly we are trying to find out. If an artist from Milan imagines a besieged Jerusalem with swallowtail merlons, the datapoint of interest is Milan, not Jerusalem. We know for certain that the VM artist drew swallowtail merlons, so what we want to find out is where artists lived who did the same. So our research question is: where were images of swallowtail merlons produced before 1450?

A second reason for our focus on imagery is that surviving buildings themselves are often unreliable. Battlements are among the first parts of ruins to crumble, and therefore they are often changed or added in restoration efforts. And many of those restorations were undertaken by the romantics of the 19th century, who were quite fond of swallowtail merlons. In other words, just because a building has them now, does not mean it had them in the 15th century.

In this thread over at we started collecting examples. A big shout out to Marco Ponzi, Aga Tentakulus and other forum members who put their shoulders behind this project. After a while, we decided to also add a “Castle layer” of actual buildings, making sure to only include those of which we are reasonably certain that they already had swallowtail merlons before 1450.

The map can be viewed below. I tried embedding it, but this requires an API, which is too much for me to handle right now 🙂 Remember that this is a work in progress:

Some more details are tracked in this thread.

The neat thing about this map is that we know for sure that the VM belongs on it as a data point among the blue markers. For all we know, it may be an outlier, but it is still interesting to see a “heat map” of known examples.