50 Fun Facts About Roman Numerals

Why did the NFL brand its February 2016 championship game Super Bowl 50 rather than Super Bowl L?

An L-only logo looked bad, the NFL's creative director admitted: the asymmetrical letter fought the standard template and risked reading as the 'loser' hand sign. The league went gold-themed instead.

Which famous London clock writes four o'clock as IV rather than the IIII most Roman-numeral dials use?

Big Ben, whose dial was designed in 1852, runs I to XII with a subtractive IV, while most Roman-numeral clock faces keep the older IIII for four yet still write nine as IX.

Roman fractions were counted in unciae, twelfths whose Latin name gave English which pair of units?

Inch and ounce both descend from uncia, the Roman twelfth: on coins, fractions below six twelfths were shown as one dot per uncia, so a five-twelfths piece carried five dots, the quincunx.

Which number does the Roman numeral MIX stand for, a numeral that happens to spell an English word?

1,009 is M plus IX with nothing written for the empty hundreds and tens: the Roman system has no zero symbol, so a missing place is simply left out, as in 207 written CCVII.

Roman numerals descend directly from the number symbols of which people, Rome's neighbours in north-central Italy?

Etruscans supplied the symbols for 1, 5, 10, 50 and 100, and like the Romans they wrote them from higher to lower value, though in their script that ran right to left.

In which year did the subtitles Episode IV and A New Hope first appear on the original 1977 Star Wars?

1981 brought the subtitles, at the film's fourth theatrical re-release, to line it up with the 1980 sequel titled on screen as Star Wars: Episode V—The Empire Strikes Back.

Why did Hollywood studios take such care over the year on a film's title screen before 1988?

A wrong numeral could void copyright under US law before the Berne Convention Implementation Act of 1988, when an incorrect or ambiguous date in the notice could even change when the copyright ended.

Why is 49 written XLIX in standard Roman numerals, and never the two-letter IL?

I precedes only V or X, so the six standard subtractive pairs are IV, IX, XL, XC, CD and CM; 49 therefore has to be 40 plus 9, and 99 is XCIX rather than IC.

Boris Yeltsin signed a document dated in the Russian style as 10.XI.'88; what does the XI stand for?

November is XI, the eleventh of the twelve: the mixed style writes that part of the date in Roman numerals and the day in Arabic ones, so 4.VI.1789 and VI.4.1789 both unambiguously mean 4 June 1789.

Which year does the Statue of Liberty's book give as MDCCLXXVI, nine letters built place by place?

1776 is M + DCC + LXX + VI: a numeral is built place by place from thousands down to units, which is why the same method renders 1918 as MCMXVIII.

After the one-off Super Bowl 50, which Roman numeral did the NFL use for the next season's championship game?

LI, for 51, picked the numerals straight back up after the golden-anniversary game at Levi's Stadium in Santa Clara, the 50th edition the league chose to mark with gold-themed branding instead.

On a Lithuanian shop's opening-hours sign written in Roman numerals, which day of the week does VII stand for?

Sunday is VII because such signs, also seen in railway and bus timetables, take Monday as the first day of the week and number it I.

Which Roman numeral spells 1066 in standard form, a year whose empty hundreds place is simply omitted?

MLXVI is M + LX + VI, with no hundreds place written at all; misplacing one letter turns it into 1046 (MXLVI) or 1064 (MLXIV), which is why each place is spelled separately.

In IUPAC names for inorganic compounds, a Roman numeral in parentheses after a metal tells a chemist what?

Its oxidation number is what the numeral states, used for cations that can carry several different positive charges; chemists once numbered periodic-table groups the same way, a habit now officially deprecated.

On a graph that includes negative numbers, which Roman-numeral region has negative values on both axes?

Quadrant III is where both axes run negative; II has only a negative x, IV only a negative y, and Roman numerals are used so the labels are never confused with the Arabic data being plotted.

A film made in 2026 would show which Roman numeral for its production year, with MM standing for 2000?

MMXXVI is MM + XX + VI; the habit of dating films this way survives on title screens even though outside references to the same film use ordinary Arabic numerals.

Which year is written MCMXCIX in Roman numerals?

1999 is M + CM + XC + IX, three subtractive pairs in a row; MCM alone signifies 1000 + 1000 − 100 = 1900, so every year of the 1900s opens with those same three letters.

Spanish writes 'siglo XVIII' and French 'XVIIIe siècle' to name which century?

The 18th century is XVIII, 10 + 5 + 3; Romance languages favour Roman numerals for centuries, as do Russian and Polish, while German and Turkish write '18.' with a full stop instead.

In a printed book, which part is conventionally page-numbered in lowercase Roman numerals such as iv and xii?

The preface, along with the introduction and sometimes the appendices, takes lowercase numerals; book volumes, chapters and the acts of a play also use them, as in Act iii, Scene 2.

In the United States, what kind of suffix is the IV in a name such as William Howard Taft IV?

Generational suffixes mark people sharing one name across generations and, like the numbers after monarchs and popes, are read aloud as ordinals: 'the fourth'.

What does a vinculum, the bar drawn above a Roman numeral, do to the value written beneath it?

Multiplies it by 1,000: the bar came into use in the late Republic and was the common way to write thousands in the Imperial era, since M for 1,000 only arrived in the medieval period.

Which principle underlies Roman numerals, so that XXVII is simply 10 + 10 + 5 + 1 + 1?

Additive is the principle: a numeral's value is the sum of its symbols, each keeping a fixed value wherever it sits, unlike place-value Arabic digits where a 2 can mean 2, 20 or 200.

The NFL's practice of naming its championship game with Roman numerals was established at which game's number?

V, the fifth game, is where the practice was established; it then ran unbroken until the league paused it for the golden-anniversary game, which it marked in gold rather than with a single letter.

Which English cathedral's late-1300s clock already showed IIII for four, as most Roman-numeral dials still do?

Wells Cathedral has a clock from the late 1300s that pairs IIII with a subtractive IX for nine, the mix that modern Roman-numeral clock faces still very often copy.

How did the builders of Rome's Colosseum label entrance 44, shunning IV while using XL for forty?

XLIIII appears on gate 44 because the Colosseum's carvers used XL for 40 but systematically avoided IV, a mixed habit that persisted in inscriptions for centuries.

Which Latin word did Dionysius Exiguus write for zero alongside Roman numerals in a 525 manuscript?

Nulla stood in for zero as early as a 525 manuscript by Dionysius Exiguus; around 725 Bede or a colleague shortened it to the letter N, which apothecaries were still writing on prescriptions in the 20th century.

The Roman symbol for 1,000 drifted from a circled X to the letter M under the influence of which Latin word?

Mille, Latin for 'thousand', pulled the symbol toward M; before that the 1,000 sign was partly identified with the Greek letter phi and passed through shapes resembling Ψ and ∞.

Regnal numbers such as 'the Second' came into widespread use in England during which king's reign?

Henry VIII's reign is when numbering kings caught on in England; before that a monarch was known by an epithet, such as Edward the Confessor, and the numbers are read aloud as ordinals.

Louis XIV of France, like Charles IV of Spain, seems to have preferred which form of his number on coins?

XIIII, the four-stroke form, is what appears on the Sun King's coinage, and William IV of Great Britain did the same with IIII; a Spanish real likewise shows Charles as IIII.

Roman numerals on the stern of the clipper Cutty Sark, rising from 13 to 22, mark what in feet?

Draught marks show how deep the hull sits in the water; on the Cutty Sark the numerals climb the stern from 13 feet at the bottom to 22 at the top.

A Renaissance chronogram hid what inside a phrase by counting the letters I, V, X, L, C, D and M?

A year, encoded as a date inside the chronogram, was the hidden payload: the reader pulled out every numeral letter, added them up, and got the number the message was built around.

Which year did the French Republican Calendar count as year I, numbering every year after it in Roman numerals?

1792 became year I when the Revolution introduced the calendar; it was abandoned in year XIV, 1805, after fourteen years of Roman-numbered years.

In the old apothecaries' system of measurement, what did the symbol SS after a quantity mean?

One half is SS, a doubled form of the Roman fraction S, which on ancient inscriptions turned VIIS into seven and a half; the same pharmacy system used N for nothing.

From which century on did Roman numerals begin giving way in Europe to the positional Hindu–Arabic system?

The 14th century is when the gradual replacement began, though Arabic numerals had reached Europe from al-Andalus by the 11th century; accounts were still kept in Roman numerals into the 1400s, with the sums done on an abacus.

In entomology, the broods of which insects, on 13- and 17-year cycles, are identified by Roman numerals?

Periodical cicadas are the insects whose broods carry the numerals; the same style of Roman-numbered labels shows up in photography's Zone System and in naming the phases of ice.

In astronomy, Saturn's moon Titan carries which Roman numeral after its planet's name?

VI makes Titan 'Saturn VI'; natural satellites get capital Roman numerals appended to their planet's name, and the same lettering names US rocket variants such as Saturn V.

London 2012 was officially the Games of which Olympiad, written in Roman numerals?

XXX is 30: London 2012, held from 27 July to 12 August, was the Games of the XXX Olympiad, while Winter editions are numbered separately, as in the XXI Olympic Winter Games.

Which year appears as the thirteen-letter MDCCCLXXXVIII on the Cambridge Public Library in Massachusetts?

1888 is M + DCCC + LXXX + VIII, thirteen letters, a length no later year matches until 2388; the library's façade shows it in the 'standard' form rather than a variant.

Which numeral writes 2,421 in standard Roman numerals?

MMCDXXI is MM + CD + XX + I: 400 is CD, a hundred taken from five hundred, and the longhand MMCCCCXXI counts as a variant rather than the standard form.

The Colosseum's surviving numbered entrances run from XXIII up to LIIII; what number is that highest gate?

54 is LIIII in the plain-stroke style the carvers used for units, proof that the classical form was largely settled when the arena went up in CE 72–80, even if IV was shunned.

A three-sided box drawn around a Roman numeral, an extension of the vinculum, raises its value by what factor?

100,000 is the box's factor, now often printed as two vertical lines plus an overbar; a 16th-century manual still taught such notations alongside the bracket-style apostrophus for big numbers.

London's Admiralty Arch gives its 1910 date with a variant, non-subtractive 900; how does it read?

MDCCCCX spells 1910 with DCCCC where MCM would be standard; the Saint Louis Art Museum went further, carving the almost unique MDCDIII for 1903 over its north entrance.

Which 1954 film's title screen dated it MCMXLIV, a Roman numeral a full decade too early?

The Last Time I Saw Paris carried MCMXLIV, which reads as 1944; the correct 1954 is MCMLIV, and under the US law of the time such a slip carried real legal weight.

Unicode's precomposed Roman numerals, handy in vertical Asian text, run up to which number?

12 is the top of the precomposed set at code points U+2160 to U+2188, in upper and lower case, so a multi-letter numeral like XII can sit on one horizontal line in vertical text.

French texts from the 15th century wrote 99 as IIII·XX·XIX, mirroring which spoken French number phrase?

Quatre-vingt-dix-neuf is 'four-score and nineteen', exactly four XXs and a XIX; English documents did the same, writing 77 as iii·xx·xvii, 'three-score and seventeen'.

Before M came into use, what was the largest number the basic Roman symbols up to D were able to express?

899 is DCCCXCIX, and anything bigger needs a thousand sign, which the Romans supplied with an overbar or bracket-like symbols long before the medieval M.

Which number below 4,000 needs the most letters, fifteen, when written in standard Roman numerals?

3,888 is MMMDCCCLXXXVIII, every place sitting at its eight; the far larger 3,999 takes only nine letters because each 9 collapses into a two-letter subtractive pair.

Lower-case Roman numerals like iv only became possible once minuscule letters were developed in which era?

The Middle Ages produced minuscule script well after the Western Roman Empire fell, and since then a final i has often been swapped for a j, as in vij for 7.

In seismology, which earthquake intensity scale expresses its degrees in Roman numerals?

Mercalli intensity scale degrees take Roman numerals, a habit shared by the phases of polymorphic crystals such as ice and by the brightness zones of photography's Zone System.

The Greek Old Testament is nicknamed LXX after the legendary number of its translators; how many was that?

70 is LXX, from septuaginta, Latin for 'seventy', which gave the translation its name Septuagint; theology texts still cite it with the bare numeral.