Why Is It Legio XIIII and Not XIV?

One of the most common questions we hear at events once people see our Vexillum (flag) is simple:

“Why do you write it as XIIII instead of XIV?”

Most of us learned in school that the Roman numeral for fourteen is XIV. While that form is certainly correct today, the Romans themselves were not always as strict about numeral conventions as modern textbooks suggest. In fact, if you look at surviving Roman inscriptions, military monuments, coins, and tombstones, you’ll find that the Fourteenth Legion was very often written as Legio XIIII, not XIV. Numerous inscriptions associated with the Legion use the additive form “XIIII” and this spelling appears throughout the unit’s history.

The reason is that Roman numerals were not fully standardized. Both additive forms (XIIII) and subtractive forms (XIV) existed side by side. The same phenomenon can be seen elsewhere in the Roman world. For example, the number four was frequently written as IIII instead of IV, including on many sundials and even on modern clock faces that preserve the ancient tradition.

For reenactors and living historians portraying the XIIII is not an error. It’s actually the form most commonly associated with the Legion in the archaeological record. When you see Legio XIIII Gemina Martia Victrix, you’re seeing a spelling that Roman soldiers themselves would have recognized. So while XIV may be familiar to modern eyes, XIIII has a strong claim to being the more authentic choice for the Legion that fought under Caesar, helped conquer Britannia, and stood against Boudica.

In short: XIV is modernly accepted, but XIIII is historically attested, and that’s why we proudly carry the name Legio XIIII.

Legio XIIII, Protinus!