Unrelated to the article's thesis: the use of both colors and numbers in the static map of the Roman Empire is very clever and I wish this technique were used m

Unrelated to the article's thesis: the use of both colors and numbers in the static map of the Roman Empire is very clever and I wish this technique were used more often. I don't in general have trouble distinguishing colored areas when they're adjacent to each other. But when they're separated from each other -- as is often the case with a map and its legend -- it becomes a lot more difficult. Using colors to show extent and numbers to match up with the legend is a great solution to this problem. Take note!