2 October 2026
Bonus post!
As part of our unit on spatial data our class was tasked with creating our own maps in Google My Maps. I was originally going to use the map I started last week on Pierre-Jacques Volaire’s paintings of Vesuvius, but I realized that my project didn’t warrant spatial analysis on the scale this assignment required. I had intended to map the different vantage points from which Vesuvius was painted from in the late eighteenth and early nineteenth centuries, but I didn’t have a large enough sample dataset beyond Volaire to comprehensively achieve that. (Volaire painted from approximately four different locations from 1767-1799).
Pivoting, I instead elected to return to my roots: Pompeii.
I decided to use a dataset that already existed for this Google My Maps project, so I downloaded the data from my Roman Wall Painting Index (RWPI) collection. As of writing, there are approximately sixty paintings uploaded onto the site, representing a small fraction of Roman wall painting still in existence. My goal was to do the opposite of the RWPI: represent this corpus of wall painting spatially rather than thematically. Of course, there are already a number of sources that organize Roman wall painting by find spot including PompeiiInPictures and Pompei: Pitture e Mosaici (1990-2003), so this is by no means a new idea.
My goal was to map the paintings by wall painting style—an organizing system originally developed by archaeologist August Mau in the nineteenth century. Mau’s system sorted Roman wall painting into four categories based on their subject content, which roughly aligned with the periods in which they were painted. Mau argued for a linear development of wall painting, from the masonry style that mimicked real wall materials like marble that was popular in the 3rd-1st centuries BCE to the more intricate figural and architectural styles popular in the 1st century CE. For a more detailed timeline with examples, see here–>.
| Style | Title | Dates | Notes |
| First | Encrustation style | 150-80 BCE | |
| Second | Architectural style | 80 BCE-14 CE | End date denoted by death of Augustus (14 CE) |
| Third | Ornamental style | 14-62 CE | End date denoted by earthquake of 62 CE |
| Fourth | Intricate style | 62-79 CE | End date denoted by eruption of Vesuvius |
The downloadable version of the RWPI data lacks spatial data, so I had to manually add that into the CSV before uploading it to Google My Maps. The find spot is listed in the data, so I went to Google Maps and pulled coordinates for the buildings that are tagged on Google (i.e. the House of the Vettii/Casa dei Vettii). For the lesser-known buildings (especially those that are not publicly accessible in the archaeological park), I had to reference published maps of Pompeii and compare it to traditional Google Maps.
This was the first major flaw of Google My Maps that I ran into. In other spatial data programs (i.e. ArcGIS Pro or QGIS), I would normally georeference a map imported into the software as a raster layer, allowing me to line up the image with its actual location on earth. Google My Maps doesn’t have the capability for georeferencing or importing raster layers, so I had to pull the coordinates the old-fashioned way.
One the paintings had spatial data, I uploaded the dataset into Google My Maps directly as a Google Sheets. You can also upload data as a CSV, but the dataset I was working with was already in Sheets format—and I don’t plan to do anything else with it—so I just kept it in G-Suite. I did have to manually split the RWPI data into two smaller datasets based on the wall painting style identified in the data, which was a little annoying. Since I intended to have two layers in my map (a “Third” and a “Fourth” style layer), I needed to upload two separate datasets into Google My Maps. For third style, see here–>. For fourth style, see here–>.
Once the paintings were placed in the map, I also went through and manually drew polygons for each of the nine regions (regio, sg.) used in the standard organization of Pompeii. Once again, Google My Maps didn’t allow for georeferencing, so I had to manually reference a map of Pompeii using one available on PompeiiInPictures. I matched up the street names within the archaeological park to the ones available on the reference map, getting the polygons as close as I could.
My map is visually appealing but analytically insignificant. The blue points represent the Third Style paintings and the red points are Fourth Style. From an initial glance at the map, there doesn’t seem to be a significant spatial distribution difference between the wall painting styles across the cities. The majority of paintings are concentrated in the northwestern part of the city, in regions VI and VII. There are some examples of third style farther east in regions V, IX, and I, but these are few and far between.
Much of the spatial distribution is limited by the relative incompleteness of the RWPI dataset. As of download, there are only approximately sixty paintings catalogued, which is a small subset of the total amount of wall painting that exists. The dataset is intentionally skewed towards third and fourth style painting as well, partly due to the goals of the RWPI (to catalogue figural subjects of paintings, which emerged in early third style) and the relative scarcity of earlier styles due to age. Many earlier paintings were replaced over time as tastes changed.
Many buildings in Pompeii were renovated after the earthquake that struck the region in 62 CE, leading to the seemingly large amount of late third and fourth style painting that existed at the eruption of Vesuvius in 79 CE. Moreover, the buildings in the northwestern parts of Pompeii were generally newer and owned by wealthier individuals in the city, further contributing to the larger proportion of newer painting styles present there. The western regions are also completely excavated, whereas the eastern regions of IV, V, IX, and III are still partially, if not mostly, unexcavated. New discoveries coming out of Regio IX have revealed numerous later style paintings, suggesting they are also present in large quantities there.
If the goal of my map was to see where wealth was in Pompeii, and we’re determining wealth by the presence of the most fashionable wall paintings of the time, my map would suggest that wealth is concentrated in the northwestern regions of the city. But my dataset is incomplete, and very skewed towards a certain part of the city, so maybe the presence of later styles of wall painting isn’t a great metric to understand wealth distribution in Pompeii.
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