The history of Roman numerals follows the history of ancient Rome itself, from its beginnings at the Latin Palatine Hill in 8th and 9th century B.C. to it's fall in the 2nd Century AD from civil war, plague, civil apathy and the rise of Christianity and northern European powers.
Growth of Mathematics, Money and Accounting
The Roman empire had inspirational, industrious and intellectual beginnings. Emperor Domitianus, Aristotle, Aristarchus, Eratosthenes, Euclid and Archamedes helped to build Rome into an ancient power, developing sophistocated intellectual and mathematical skills to build the Colosseum, Constantine's Arch, Pantheon, Roman Baths and Civil society.
However, their number system was flawed, it had no zero (0), and no single method for counting above several thousand units, (lines were often placed over numerals to indicate multiples of their value).
The eventual fall of the Roman Empire by 300 A.D. saw the introduction and adoption of Arabic numerals, today we call them decimal numbers because they work consistently to a base of 10. The invention of zero (nothing) was a huge leap forward.
Uses of Roman numerals
Roman numerals today are used most frequently seen as list numbers, time pieces and historic Roman coins, art and antiquities in museums and antique shops. Nearly all computer word processing packages (Word, PDF) allow uppercase and lowercase Roman numerals as list item indicators.
Roman numerals or numbers are also used in classic style watch and clock faces where the Roman number for 4 is often written as IIII rather than IV, to add symmetry and balance to the face. Quite often you can see numerals used to indicate the time on sundials.
Uses in the Media
Typically books have chapter headings as numerals, and number their forward pages with them to indicate that it is the page forward. In other media such as Films and Television copyright dates are in numerals, for example the BBC production dates, but also in films to denote film sequels, such as Rocky III.
Ancient but Here to Stay
Roman numerals have a long history and are here to stay! Even though we struggle to remember larger numbers we enjoy their classic style and elegance.