Much before the Hindu-Arabic number system that we use today came into widespread use throughout the West, people largely used Roman numerals. It was a system that was developed by the ancient Romans. Instead of using numbers, they created a set of symbols or letters that coincided with certain numbers. For example, I indicated 1, V was for 5, X for 10, and so on. By grouping letters together, they could make new numbers, so that IV was 4, or XI was 11. A major flaw in the system of Roman numerals was that it did not include any symbol for zero, so that many calculations were impossible to carry out. Even so, the influence of this powerful civilization was so strong that the Roman numeral system was the dominant numbering system used through the West for several centuries. In this way, it lasted up until the 14th century! By the Middle Ages, Roman numerals were still used, but with some modifications. Instead of only using capital letters, people adopted the practice of using lower-case letters, so that 1 could either be written as I or i, while 4 might be IV or iv. People in those times took it one step further by adopting other Roman letters for additional numbers. For instance, where there was previously no specific number for 7 (except to group V and II together), the Medieval mathematicians took to signifying it with an S or Z. Similarly, many other letters of the alphabet came to be used for numbers.

While Arabic numerals are the predominant way of counting today, Roman numerals are still used in modern times in several areas. Often, it is used for nostalgic, decorative, or ceremonial purposes, such as on clocks, building faces, book chapters, copyright notices, the names of politicians and monarchs, major seasonal events, and so on. Roman numerals persist in several traditional fields that include medicine, music, chemistry, and astronomy. For many students (and even adults!), learning to identify and calculate Roman numerals can be quite a challenging task. It does take quite a bit of practice to be able to deftly read and calculate in this ancient numbering system. Apart from the basic numbers that are commonly known, there are also several other special characters and methods of denoting larger numbers. Keep in mind too that in reviewing examples of Roman numerals in older texts, they may be written in different ways since the notation methods evolved from one century to the next.

However, since Roman numerals are still used in so many areas today, it is important to be able to read and count them. A fun way to make students excited about learning Roman numerals is to present it as a sort of secret code. Their interest will be piqued and they will tend to attack the problems as a challenge rather than as tedious schoolwork. To demonstrate what an ancient system it is, try to show them examples of Roman numerals on real world items. A trip to a coin collector’s store might uncover shining examples of Roman numerals displayed on antiquated coins. Alternatively, set up a scavenger hunt field trip, where the students can tour the town or neighborhood to try and find Roman numerals that are still used and displayed in public areas. Have a look at the following collection of resources for educators to get started with background history, reading and calculation guides, plus a series of worksheets, handouts, quizzes, videos, and other fun educational materials!

Roman Numeral History

Reading Roman Numerals

Roman Numerals Educational Materials