History and Literature | Latin Words and Grammar

Iacta Alea Est: Crossing the Rubicon

This article has been reviewed in accordance with our editorial policy.

On Jan­u­ary 10th, 49 B.C., Gaius Julius Cae­sar uttered one of history’s most famous lines, Iac­ta alea est (some­times writ­ten alea iac­ta est), after which he crossed the Rubi­con riv­er with his army and set the Roman Civ­il War in motion.

A Well-Known War

Thou­sands of pages have been writ­ten about Julius Cae­sar, Pom­pey and the Civ­il War fought between them. Movies have been made, books have been writ­ten, TV-series produced,so we shall not dwell too long on the issues of war.

How­ev­er, in order to get a good grasp of the mean­ing of Caesar’s enor­mous­ly famous expres­sion, let me just give you a short recap of the story.

JULIUS CAESAR AND THE CROSSING OF THE RUBICON, FRANCESCO GRANACCI, 1494. COURTESY OF VICTORIA AND ALBERT MUSEUM.

Caesar’s Command

In the 50’s B.C. there were some polit­i­cal ten­sions between Cae­sar and Gnaeus Pom­peius Mag­nus, also known as Pom­pey, a man he had pre­vi­ous­ly been in an alliance with.

The alliance between Cae­sar, Pom­pey and Mar­cus Licinius Cras­sus had been an infor­mal coali­tion, know to his­to­ry as the First Tri­umvi­rate.  Cras­sus, how­ev­er, fell in the bat­tle of Car­rhae in the Parthi­an war.

Sug­gest­ed read­ing: Omnia Vincit Amor: Love in Ancient Rome

At the time of his famous quote, Cae­sar had for 9 years suc­cess­ful­ly been cam­paign­ing in his provinces north of Italy – Cisalpine Gaul, Transalpine Gaul and Illyricum – gain­ing quite a lot of popularity.

VERCINGETORIX THROWS DOWN HIS ARMS AT THE FEET OF JULIUS CAESAR. PAINTING BY LIONEL ROYER, 1899. THE PAINTING DEPICTS THE SURRENDER OF THE GALLIC CHIEFTAIN AFTER CAESAR’S VICTORY IN THE BATTLE OF ALESIA IN 52 B.C.

For quite some time, he had moved with­in a rather grey area, legal­ly speak­ing; by 51 B.C. the Sen­ate wished to replace him as gov­er­nor of Gaul and decid­ed that his army should be dis­band­ed by Novem­ber 13, 50 B.C. (Rond­holz, p. 433)

Cae­sar pro­posed that he would lay down his com­mand over Gaul if Pom­pey gave up the com­mand he held over Spain. This was ignored. (Board­man, Grif­fin & Mur­ray, p. 94–97; Boatwright, Gar­go­la & Tal­bert, p. 145–157; Jones & Sid­well, p. 42–43)

Cae­sar was declared an ene­my of the state on Jan­u­ary 7th 49 B.C. (Rond­holz, p. 433)

JULIUS CAESAR BY ANDREA DI PIETRO DI MARCO FERRUCCI, 1512–14.

Leading A Legion

On Jan­u­ary 10, 49 B.C. Gaius Julius Cae­sar led Legio XIII, the thir­teenth legion, from Raven­na in north­ern Italy over the riv­er Rubi­con towards Armini­um (mod­ern Rim­i­ni) and on towards Rome.

The Civ­il War was a fact.

But why was this move so important?

The polit­i­cal envi­ron­ment had for a long time been infect­ed and war was immi­nent, so how come cross­ing over a small, rather insignif­i­cant riv­er was to become the sym­bol for the end of the Republic?

Treason

As gov­er­nor Cae­sar held the right to com­mand troops with­in his own provinces, i.e. Gaul, but not with­in Italy. Italy answered to Rome and Rome alone.

This meant that Cae­sar, by law, was for­bid­den to com­mand an army in Italy.

CISALPINE GAUL, EXTENDING FROM VENICE BY THE ADRIATIC SEA, TO PISA AND NICE BY THE MEDITERRANEAN, TO LAKE GENEVA AND THE ALPS, MAP FROM ABRAHAM ORTELIUS THEATRUM ORBIS TERRARUM, ANTWERP, 1608.

The riv­er Rubi­con has nev­er been a large riv­er. It wasn’t a hard riv­er to cross. There were no casu­al­ties from try­ing to fight hard cur­rents or any­thing like that. Instead, the Rubi­con was a border.

The Rubi­con marked the bor­der between Caesar’s province, Cisalpine Gaul to the north-east, and Italy itself. Cross­ing the riv­er meant cross­ing the bor­der into Italy.

Cross­ing the bor­der still in com­mand of your troops, meant break­ing the law.

It meant treason.

It meant war.

Not only did Cae­sar him­self break the law as the gov­er­nor and com­man­der, but his army broke the law by fol­low­ing a man who had no author­i­ty of command.

The Cry And Cast Of Caesar

There are sev­er­al Roman sources that inform us about this event, but our Latin quote, the mem­o­rable Iac­ta alea est, comes from the his­to­ri­an Sue­to­nius’ biog­ra­phy De Vita Cae­sarum: Divus Iulius.

Accord­ing to Sue­to­nius, after some hes­i­ta­tion at the riv­er, Cae­sar was giv­en a sign by the gods as an appari­tion, play­ing a reed pipe, snatched a trum­pet from a by-stand­ing sol­dier and sound­ed a bat­tle sig­nal. Cae­sar then cried out:

“‘Eatur,’ inquit, ‘quo deo­rum osten­ta et inim­i­co­rum inquitas vocat. Iac­ta alea est.’ ”

— Sue­to­nius, De vita Cae­sarum, lib I, xxxii

i.e. “Take we the course which the signs of the gods and the false deal­ing of our foes point out. The die is cast.” (transl. Rolfe, 1914)

You can down­load the audio & a PDF. Get the Latin audio of Sue­to­nius’ “alea iac­ta est”-passage as well as a print-ready PDF with the text. Click Here.
LE PASSAGE DU RUBICON PAR CÉSAR BY JEAN FOUQUET, 1420–1480

The Die Is Cast

Tra­di­tion­al­ly Iac­ta alea est has been trans­lat­ed into “the die is cast” and used as a way of indi­cat­ing that some­thing has passed a point of no return, or that you have made your move and that things are now out of your hands and there is no turn­ing back.

Some 300 years after Cae­sar’s excla­ma­tion we find a ver­sion of the phrase with Ammi­anus Mar­celli­nus (330–400 A.D.): “aleam per­icu­lo­rum omni­um iecit abrupte” (Amm., XXVI, xii) i.e. “haz­ard­ed at one cast all per­ils” that illus­trates this perfectly. 

How­ev­er, it can be argued that oth­er trans­la­tions would suit better.

Game Or Die

As Cae­sar uttered these words the point of no return had not yet been reached, he had not yet made his move, because he said Iac­ta alea est BEFORE he crossed the riv­er, not afterward. 

To be fair, the deci­sion had been made.

How­ev­er, the word alea does not just mean “die” (i.e. the num­bered cube used in gam­ing), it is also the game of dice itself or, more broad­ly, a game of hazard/chance.

A die was called tessera or talus in Latin depend­ing on the amount of num­bered sides.

A tessera had six sides, like our nor­mal die, and the talus had four marked sides and two round­ed unmarked.

A TESSERA OR A ROMAN SIX-SIDED DIE FROM THE VIDY ROMAN MUSEUM. PHOTOGRAPHED BY RAMA.

We find a good exam­ple in Plautus:

“talos posc­it sibi in manum,
provo­cat me in aleam”

— Plau­tus, Cur. 354–355

i.e. “he asked for dice and chal­lenged me to play a game.”

Accord­ing to Isidore of Seville (560–636) –who wrote an ety­mo­log­i­cal ency­clo­pe­dia on every­thing– alea is a boardgame with dice, invent­ed dur­ing the Tro­jan war by a sol­dier named Alea – hence the name. To be tak­en with more than a grain of salt, to be sure.

”Alea, id est lusus tab­u­lae, inven­ta a Grae­cis in otio Troiani bel­li a quo­dam milite Alea nomine, a quo et ars nomen accepit. Tab­u­la ludi­tur pyr­go, cal­culis tesserisque.” – Orig. XVIII, lx

But there are also a few exam­ples where alea is used to describe the die, not the game.

Game On

Per­haps stick­ing to the tra­di­tion­al use and trans­la­tion of the proverb ”the die is cast” is the way to go. Where an irrev­o­ca­ble choice or deci­sion has been made and the point of no return has been passed.

Per­haps anoth­er good trans­la­tion would be some­thing along the lines of “Game on!”, “The game is afoot.” or ”Let the game be ven­tured!”, as Lewis and Short pro­pose in addi­tion to the more tra­di­tion­al translation.

Maybe that was what ran through the mind of Cae­sar just before he stepped into the riv­er – “Game on, Pom­pey, game on.”

We will nev­er know.

What do you think?

DICE PLAYERS, ROMAN FRESCO FROM THE OSTERIA DELLA VIA DI MERCURIO IN POMPEII.

Did He Actually Say It?

Now, I’ve been writ­ing like Cae­sar actu­al­ly uttered these famous words. But did he really?

We don’t know.

Maybe it is just an author’s wish to spice up the sto­ry of Cae­sar mov­ing yet more troops from one place to anoth­er. Maybe not.

Cae­sar him­self does not men­tion the expres­sion it in his Bel­lum Civile. He does not even men­tion cross­ing the Rubicon.

Instead, he briefly states being in Raven­na, moves on to sum­ma­rize his address to his sol­diers and then swift­ly men­tions set­ting out with the thir­teenth legion for Armini­um. (Bel. Civ. 1.5–1.8). But noth­ing about the Rubi­con, which is sup­posed to be some­where in between these two towns.

What Say The Ancients?

Cicero, con­tem­po­rary of Cae­sar, does not men­tion Rubi­con or the cast of the die in his letters.

Nei­ther does the his­to­ri­an Livy in his Ab Urbe Con­di­ta, writ­ten only 17 years or so after the event. (Tuck­er, p. 246) The rel­e­vant vol­ume (liber 109), how­ev­er, con­tain­ing these events is miss­ing. What we have left is the Peri­ochae, i.e. sum­maries of the book itself. The sum­ma­ry does not men­tion the Rubi­con or Iac­ta alea est, the book might have.

Anoth­er Roman his­to­ri­an, Mar­cus Velleius Pater­cu­lus (c. 19 B.C.- c. 31 A.D.), men­tions Rubi­con, but not the expression:

“…ratus bel­lan­dum Cae­sar cum exerci­tu Rubi­conem transiit.”

— Velleius, 2.49

i.e. ”Cae­sar con­clud­ed that war was inevitable and crossed the Rubi­con with his army.” (transl. Ship­ley, 1924)

THIS IS THE TITLE PAGE OF A FRENCH EDITION OF LUCANS PHARSALIA FROM 1657 WHERE CAESAR’S MEETING WITH THE PERSONIFIED ROME IS DEPICTED.

The poet Mar­cus Annaeus Lucanus, or Lucan, has Cae­sar meet with a white-haired, sad-faced per­son­i­fi­ca­tion of Rome to ask Cae­sar not to go fur­ther. Instead of the famous Iac­ta alea est, Cae­sar says:

“Hic,” ait, “hic pacem temer­ataque iura relinquo;

Te, For­tu­na, sequor. Procul hinc iam foed­era sunto;

Cre­didimus satis his, uten­dum est iudice bello.”

(Lucan, Pharsalia, lib. I, 225–7)

SUETONIUS IN THE NUREMBERG CHRONICLES, 1493.

i.e. “Here,” he cried, “here I leave peace behind me and legal­i­ty which has been scorned already; hence­forth I fol­low For­tune. Here­after let me hear no more of agree­ments. In them I have put my trust long enough; now I must seek the arbitra­ment of war.” (transl. Duff, 1928)

And Sue­to­nius, well he wasn’t even born at the time of the Civ­il war. He was born in 69 A.D. long after Cae­sar crossed the Rubi­con and long after he had been murdered.

Local Latin Or Greek-Speaker

We have sev­er­al more accounts about Cae­sar and his march­ing across the riv­er Rubi­con, these, how­ev­er, are not in Latin as all the pre­vi­ous, but in Greek.

Lucius Mestrius Plutarchus, or Plutarch, 46–120 AD, is the first one, to our knowl­edge, to have put the words Iac­ta alea est into the mouth of Caesar.

He wrote it in three dif­fer­ent texts: 

“ἀνερρίφθω κύβος”

— Plutarch, Moralia 206.7; Caes. 32; Pomp. 60

In one of them, Life of Pom­pey, he added that Cae­sar uttered the words in Greek, not in Latin.

PLUTARCH IN THE NUREMBERG CHRONICLES, 1493.

Appi­anus Alexan­dri­nus, or Appi­an, born even lat­er than Plutarch in 95 A.D. was a Greek his­to­ri­an with Roman cit­i­zen­ship who wrote about the Civ­il War. He called Cae­sar’s famous excla­ma­tion, “ὁ κύβος ἀνερρίφθω.”, a famil­iar phrase. (Civ­il Wars 2.5.35)

Is Plutarch’s claim true? Did Cae­sar utter his famous words in Greek? 

Again, we don’t know. It could be. The Roman elite was known for speak­ing Greek, like the Swedish or Russ­ian nobil­i­ty pre­ferred to speak French in the 1700’s, so did the Roman nobil­i­ty speak Greek.

But to be frank: we don’t know.

What we do know is that the quote Plutarch had Cae­sar say, pre­dates both Plutarch, Sue­to­nius and Caesar.

Proverb Of Playwrights

The expres­sion is found in two frag­ments from ancient Greece.

One is a small frag­ment from the Greek play­wright Menan­der (c. 341 – c. 290 B.C.): 

MENANDER FRAGMENT 65, YOU’LL FIND OUR EXPRESSION AT THE END OF LINE 4. (KOCK, VOL III, P. 22.)

The oth­er is an old­er, even small­er frag­ment from none oth­er than the famous play­wright of ancient Athens, Aristo­phanes (c. 446 B.C. –c 386 B.C):

ARISTOPHANES FRAGMENT 673. (KOCK, VOL I, P 557.)

So, the proverb, or expres­sion, that Plutarch, Sue­to­nius and Appi­an put on the lips of Julius Cae­sar is most like­ly a very old one. And per­haps he uttered the words in Greek, per­haps in Latin, per­haps not at all.

Unfor­tu­nate­ly, we do not have access to Livy’s book 109 of Ab Urbe Con­di­ta nor any of the oth­er sources for our sources – i.e. a biog­ra­phy of Cae­sar writ­ten by Caesar’s friend Gaius Oppius and the his­to­ry of the Roman sol­dier, politi­cian and his­to­ri­an Asinius Pol­lio, also con­tem­po­rary to Cae­sar. (Rond­holz, p. 433) So the ques­tion remains unsolved.

ILLUSTRATION FROM HISTORY OF JULIUS CAESAR BY JACOB ABBOTT, 1849

The River Rubicon

The riv­er Rubi­con nev­er had any impor­tance as a riv­er, only as a bor­der. We know that it was sit­u­at­ed some­where between Raven­na and mod­ern Rim­i­ni, but not exact­ly where.

This might seem odd but, when Octa­vian merged Cisalpine Gaul with Italy, the riv­er lost its impor­tance and its loca­tion was soon lost in the mists of history.

How can that be you ask? How can you lose the loca­tion of a river?

Well, as men­tioned, the Rubi­con has nev­er been a large riv­er – as rivers go, there are more impor­tant ones. More­over, in the area where Rubi­con is sup­pos­ed­ly locat­ed, south of Raven­na and north of Rim­i­ni, there are sev­er­al small, shal­low rivers. Also, rivers tend to change their course over time.

ILLUSTRATION OF CAESAR’S PASSAGE OVER THE RUBICON FROM LES ANCIENNES HYSTOIRES ROMMAINES, 1375–99. THIS IMAGE CLEARLY SHOWS THAT EVEN THE SIZE OF THE RUBICON HAD BEEN FORGOTTEN.

A Dictator’s Decision

By the Renais­sance inter­est in the riv­er was grow­ing amongst human­ist but it wasn’t until the 1930’s, on the ini­tia­tive of Ben­i­to Mus­soli­ni, that the Rubi­con, or Rubi­cone in Ital­ian, was offi­cial­ly iden­ti­fied as being the riv­er Fiumicino.

In 1933 Mus­soli­ni ordered the name of the Fiu­mi­ci­no to be changed. It was.

From that day, the Fiu­mi­ci­no has large­ly been accept­ed to be the Rubi­con, but not every­one has agreed.

The Right River

In August 2013, to decide on the true iden­ti­ty of the Rubi­con, a mock-tri­al was held in the small Ital­ian town of San Mau­ro Pascoli

Fight­ing for the price was the Fiu­mi­ci­no, defend­ed by Gian­car­lo Maz­zu­ca, writer and news­pa­per edi­tor, the riv­er Pis­ci­atel­lo or Urgón, as debat­ed by local teacher and jour­nal­ist Pao­lo Tur­roni, and the Uso as argued by archae­ol­o­gist Cristi­na Ravara Montebelli.

When the votes had been count­ed, Mussolini’s Rubi­con lost count­ing only 173 votes, the Uso received 215 and the Pis­ci­atel­lo or Urgón won with 269 votes. You can read more about the mock-tri­al here.

How­ev­er, Mussolini’s Rubi­con is still called Rubicon.

CAESAR ÜBERSCHREITET DEN RUBIKON, FROM BIBLIOTHEK DES ALLGEMEINEN UND PRAKTISCHEN WISSENS, 1904.

Pompey’s Passing

We don’t know if the riv­er Mus­soli­ni called Rubi­con is the real Rubi­con or if it’s some oth­er riv­er. What we do know is what hap­pened once Julius Cae­sar had crossed it and brought his legion into Italy:

War hap­pened.

As word spread of Cae­sar and his army march­ing towards Rome, Pom­pey and the Sen­ate fled. This might have seen rash, but they were blindsided.

Tra­di­tion­al­ly, war was waged dur­ing the sum­mer. Dur­ing win­ter­time, armies rested.

For Cae­sar to march the thir­teenth legion into Italy in Jan­u­ary was unprece­dent­ed and took Pom­pey by com­plete sur­prise. No one expect­ed any devel­op­ments for the win­ter. (Boatwright, Gar­go­la & Tal­bert, p. 155)

With this dec­la­ra­tion of war, Pom­pey and his asso­ciates saw only one option – flight.

And, long sto­ry short, Pom­pey was defeat­ed and killed in Egypt and Cae­sar was elect­ed dic­ta­tor for life. The Roman Repub­lic was dead.

DETAIL OF A MINIATURE OF THE DEATH OF POMPEY FROM F. 271 OF LA GRANT HYSTOIRE CESAR, E.T. LES FAITS DES ROMAINS, 1479.

References & Recommended Reading

Ammi­anus Mar­celli­nus. His­to­ry, Vol­ume II: Books 20–26. Trans­lat­ed by J. C. Rolfe, Cam­bridge, MA, 1940.

Board­man, John, Jasper Grif­fin & Oswyn Mur­ray, eds. The Oxford Illus­trat­ed His­to­ry of the Roman World, Oxford 2001.

Boatwright, Mary T., Daniel J. Gar­go­la & Richard J.A. Tal­bert, A Brief His­to­ry of the Romans, Oxford 2006.

Cae­sar. Civ­il War. Edit­ed and trans­lat­ed by Cyn­thia Damon. Cam­bridge, MA, 2016.

Cicero. Philip­pics 1–6. Edit­ed and trans­lat­ed by D. R. Shack­le­ton Bai­ley. Revised by John T. Ram­sey, Gesine Manuwald. Cam­bridge, MA, 2010.

Jones, Peter & Kei­th Sid­well, eds.,The World of Rome: An Intro­duc­tion to Roman Cul­ture, Cam­bridge, 1997.

Kock, Theodor­us, Comi­co­rum atti­co­rum frag­men­ta, vol i, 1880.

Kock, Theodor­us, Comi­co­rum atti­co­rum frag­men­ta, vol iii, 1888. 

Lucan, The Civ­il War (Pharsalia). Trans­lat­ed by J. D. Duff,Cambridge, MA, 1928.

Plutarch. Moralia, Vol­ume III: Say­ings of Kings and Com­man­ders. Say­ings of Romans. Say­ings of Spar­tans. The Ancient Cus­toms of the Spar­tans. Say­ings of Spar­tan Women. Brav­ery of Women. Trans­lat­ed by Frank Cole Bab­bitt, Cam­bridge, MA, 1931.

Plutarch. Lives, Vol­ume VII: Demos­thenes and Cicero. Alexan­der and Cae­sar. Trans­lat­ed by Bernadotte Per­rin, Cam­bridge, MA, 1919. 

Plutarch. Lives, Vol­ume V: Age­si­laus and Pom­pey. Pelop­i­das and Mar­cel­lus. Trans­lat­ed by Bernadotte Per­rin, Cam­bridge, MA, 1917. 

Rond­holz, Anke ”Cross­ing the Rubi­con. A His­to­ri­o­graph­i­cal Study” in Mnemosyne, Fourth Series, Vol. 62, Fasc. 3, 2009.

Sue­to­nius. Lives of the Cae­sars, Vol­ume I: Julius. Augus­tus. Tiberius. Gaius. Caligu­la. Trans­lat­ed by J. C. Rolfe, intro­duc­tion by K. R. Bradley,  Cam­bridge, MA, 1914.

Tuck­er, Robert A., ”What Actu­al­ly Hap­pened at the Rubi­con?” in His­to­ria: Zeitschrift für Alte Geschichte Bd. 37, H. 2, 2nd Qtr., 1988.

Velleius Pater­cu­lus. Com­pendi­um of Roman His­to­ry. Res Ges­tae Divi Augusti. Trans­lat­ed by Fred­er­ick W. Ship­ley, Cam­bridge, MA, 1924.

Amelie Rosengren

Amelie Rosengren

Amelie Rosengren, M.A. and co-founder of Latinitium, is a published author, illustrator and historian. She specializes in daily life, has a soft spot for historic curiosities, and works as a museum educator at the world’s oldest open air museum, Skansen.
Written by Amelie Rosengren

Written by Amelie Rosengren

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