You might have seen a watch or a clock with roman numerals, only to find yourself wondering why the roman numeral 4, or IV is actually written as IIII.
There is one simple answer for why modern watchmakers, including Rolex, still use this today.
Visual Balance and Dial Symmetry
In short, modern clocks and watches with roman numerals use IIII instead of IV on the dial for visual balance and symmetry. Looking at the hour markers of a watch with roman numerals, such as the Rolex Datejust, we can see how the IIII hour marker helps divide the dial into three different, balanced sections:
- 1:00 to 4:00, displayed as I, II, III, and IIII.
- 5:00 to 8:00, displayed as V, VI, VII, VII.
- 9:00 to 12:00, displayed as IX, X, XI, and XII.
The first third of the dial uses I, the second uses V, and the third uses X.
Further, the IIII on a watch is opposite to VIII, and is much more symmetrical than IV is to VIII. Ultimately, this creates a more visually appealing and balanced feeling dial that is more appealing to look at.
With that said, that doesn’t answer the question of how or why this started, and there are quite a few theories.
The History of Roman Numeral 4 as IIII on Clocks
One theory stems back to the late 14th century, when King Charles V, the king of France told a watchmaker to replace IV with IIII on a clock. IV is denoted as 4 by subtracting 1 from 5, in King Charles’ mind, undermining his name. (source)
One theory suggests that IV was not easily understandable in the middle ages, where not as many people were as educated to read or write in plain English, let alone in roman numerals.
Another theory dips into Roman mythology. Rome’s supreme deity, Jupiter, was spelled “IVPITER” in Latin. The Romans might not have felt comfortable engraving part of their god’s name on sundials or even in books.
Ultimately, the 4:00 roman numeral on modern clocks and watches is denoted as IIII instead of IV to create a more symmetrical and balanced dial. While this is a practice that has been seen throughout history on watches, clocks, and even when writing names, it remains true that the main reason, in this day and age, is a more practical and aesthetically driven one.