Napoleon's Commentaries on the Wars of Julius Caesar

A New English Translation

Napoleon Bonaparte, R.A. Maguire

• Publisher: Pen & Sword Military
• Year: 2020
• Print ISBN: 9781526716279
• eBook ISBN: 9781526716293
• Topic: History
• Subtopic: Military & Maritime History
• Index: History

While in exile on St Helena, Napoleon dictated a commentary on the wars of Julius Caesar, later published in 1836. In each chapter he summarized the events of one campaign, then added comments from the standpoint of his own military knowledge. Over the nearly two millennia between Caesar and Napoleon some aspects of warfare had changed, notably the introduction of firearms. But much remained the same: the rate of movement of armies (at the foot pace of horse or man); human muscle power as the main source of energy for construction work; some military techniques, notably bridge construction; as well as the actual territory fought over by Caesar and later by Napoleon. Napoleons commentary thus provides a fascinating and highly authoritative insight into Caesars wars, as well as providing a window into Napoleons own thinking and attitudes. Napoleon in places detects mistakes on the part of Caesar and his enemies, and says what they should have done differently. Remarkably, this is thought to be the first full English translation of Napoleon's work.Napoleon Bonaparte was born to an obscure Corsican family but rose through the ranks of the French army to become Emperor of France, conqueror of most of Europe and acknowledged military genius. He wrote this book while in exile on St Helena.The translator. RA Maguire, is a former civil engineer with a long-standing interest in military and ancient history.

Chapter 1

Gallic War. First campaign (58 BC)

I. Caesar

Caesar was born in 100 BC and died in the year 44; he lived for 56 years. He was only 16 when he suffered under the persecutions of Sulla. He first bore arms under the praetor Thermus, earned the Civic Crown at the capture of Mitylene, travelled to Cilicia, stayed at the court of King Nicomedes in Bithynia, was held prisoner by pirates for forty days, returned to Rome after the death of Sulla, prosecuted Dolabella (a man of consular status), failed in his attack, withdrew to Rhodes and studied rhetoric at the famous school there.

On his return, the people successively appointed him military tribune, quaestor, aedile and pontiff. He pronounced the funeral oration of his aunt Julia, his father’s sister and wife of Marius. The Roman people were pleased to see the image of Marius amongst the images of the Julii; later he placed on the Capitol the statue of this famous vanquisher of the Cimbri, which earned him the disapproval of the Senate. He obtained the recall of Cinna, his father-in-law, who had been proscribed along with Sertorius. He condemned to death Sulla’s assassins, the murderers of the proscribed.

The people, who revered him, elected him praetor in the year 62.1 His magistrature was stormy and the Senate declared against him. He governed Cisalpine Gaul2 and, a year later, Spain, as propraetor. He commanded thirty cohorts in Portugal. His army proclaimed him Imperator. On return to Rome, he sought both a triumph and the consulship. He concluded with Pompey and Crassus the pact known as the first triumvirate and married his daughter Julia to Pompey, who became deeply enamoured of her.

Appointed consul for the year 59, he conducted himself like a people’s tribune, published agrarian reform laws, distributed land to the poor and recognized Ptolemy, King of Egypt and Ariovistus, King of the Suebi, as friends of the Roman people. The Senate opposed him at every turn. He was leader of the Marian faction.

In 58, he was appointed governor of Illyria and Cisalpine Gaul for five years: he was given three legions. A few weeks later, he added to these governorships that of Transalpine Gaul, with a fourth legion. He also raised two new legions; the one named ‘the Larks’, composed of Gauls, was to distinguish itself. He began the Gallic war with six legions; during the course of the war the number rose to twelve.

Caesar conducted eight campaigns in Gaul, as well as two invasions of Britain and two incursions onto the right bank of the Rhine. In Gaul, he fought nine major battles, conducted three important sieges and reduced 500 miles of territory to the status of Roman provinces, thereby enriching the treasury by eight millions of ordinary contributions.3 During the Civil War, Caesar fought in Italy, Spain, Illyria, Egypt, Asia and Africa in the years 49, 48, 47, 46 and 45; he fought six major battles, of which four were against Pompey’s Roman legions and two against barbarians. During these thirteen campaigns, he was beaten three times, at Dyrrachium, Alexandria and in Africa; but these setbacks had no effect on the outcome of his wars. His lieutenants suffered some serious defeats, which he reversed by his presence.

II. Helvetian war

Gaul was divided into four parts: the Belgian, Celtic and Aquitainian regions, and lastly the Roman province.4 Belgium lay between the Seine, the Rhine and the sea; the Celtic region between the Seine, the Rhône, the Garonne and the ocean; Aquitaine, between the Garonne and the Pyrenees; Roman Gaul comprised the Dauphiné, Savoie, Lyonnais, Provence and a part of Lower Languedoc on the Mediterranean coast.

Caesar’s authority extended over both Transalpine and Cisalpine Gaul, including the entire Po valley; it was bordered in the east by the Rubicon, in the Romagna, and in the west by the Magra, near the Gulf of Spezia. Thus he had under his authority the defence of all of Italy’s land frontiers, the entire barrier of the Alps and also the provinces of Illyria.

Gaul was composed of petty states which were governed as republics and could ally together in the common interest. Assemblies of the whole nation took place in the territory of Chartres. The Gauls crossed the Alps and invaded Northern Italy six or seven centuries before the Christian era; there they founded the cities of Milan, Mantua, Verona and others; this country was called Cisalpine Gaul. The Romans entered Gaul for the first time in 209 BC. Invited by the people of Marseille, they crossed the Var, following the Corniche in order to avoid the Alps. In 123 BC, the consul Sextius built Aix-en-Provence. The following year, the people of Autun appealed to the consul Domitius for aid against the people of Auvergne, who were allied to the Allobroges, or people of Dauphiné.

The armies met near Avignon, where the Romans were victorious. The next year, a further battle took place at the confluence of the Isère and the Rhône; the Gauls were again beaten, and many drowned in the river. Dauphiné and Provence then became a Roman province. Some years later, Rome founded a colony at Narbonne, which extended its dominion into Languedoc.

In the present year, 58 BC, the Helvetians, or Swiss, and the people of Breisgau resolved to leave their country and migrate to Saintonge, near to the shores of the ocean. They burnt twelve of their towns and 400 of their villages, provided themselves with enough flour for three months, and 368,000 people, of whom 90,000 could bear arms, set off with their carts and possessions. Caesar, who had just been given authority over Gaul, hastened forward, reached Geneva on the eighth day and had the bridge over the Rhône broken down. There was only one legion in the province; he summoned the three old legions which were in Illyria as well as the two new legions which he had raised. He constructed a fortification 16ft high and 14 miles long from the Rhône to the Jura mountains. While he was undertaking these defensive preparations, the Helvetians sent to ask him to allow them passage across the Roman province: he sent back a refusal on 13 April (23 January).5 The Helvetians, despairing of forcing the fortifications, appealed to the people of Franche-Comté who were more accommodating. They crossed the Jura and arrived at the Saône. Meanwhile, Caesar had re-crossed the Alps in order to speed up the march of his legions. At their head he entered Lyon, reached Chalon-sur-Saône, surprised the people of Zurich who were encamped on the left bank of this river, destroyed them entirely, set off in pursuit of the rest of the Helvetians and followed them for fifteen days with six legions and a body of cavalry from the town of Autun. At one day’s march from this town, the Helvetians launched a surprise attack: they were a dauntless people. Caesar only had time to place his four experienced legions in a three-line battle order halfway up a hill, and the two new legions with the baggage at the summit. After a most stubborn combat, the Helvetians were beaten; they decamped in the night, and four days later arrived near Langres, pursued by Caesar, who spared them, obliging them to return to their own country and rebuild their towns. These peoples were reduced to less than a third of their original number (130,000).6

III. War with Ariovistus

Ariovistus, King of the Suebi, had been declared a friend of the Roman people. Invited into Gaul by the people of the Auvergne and Franche-Comté, he defeated the people of Autun and their allies in a battle near Pontarlier, and compelled all these little republics to pay him tribute and provide him with hostages. Later he extended his impositions to the people of Franche-Comté itself and appropriated a third of their territory, which he distributed to 120,000 Germans. A still greater number, attracted by this allurement, were preparing to cross the Rhine; 24,000 had departed from Constance and the 100 cantons of the Suebi had already reached the banks of the river. Gaul was about to be shaken to its foundations and had to seek Roman help.

Caesar demanded a meeting with Ariovistus. The reply being unsatisfactory, he crossed the Saône and surprised Besançon. After some days of rest, he continued his march in the direction of the Rhine. On the seventh day, after a detour to avoid mountains, the two armies came together. Caesar and Ariovistus met, but nothing was resolved. The Germans were men of tall stature, strong and brave. After some manoeuvring, the two armies fought on a battlefield 40 miles from the Rhine. Ariovistus was beaten and his army pursued as far as the river, which the king crossed in a small boat. This disaster astounded the Germans and saved Gaul. Caesar then crossed the Alps, leaving his army in its quarters under the command of Labienus.

Thus, in this first campaign, he won two great battles against the Helvetians and the Suebi under Ariovistus, to whom were joined the peoples of Constance, Bohemia, Strasbourg and Mayence.

IV. Observations

1. Caesar took eight days to travel from Rome to Geneva: today this journey could be completed in four days.

2. The ordinary field fortifications of the Romans consisted of a V-shaped ditch 12ft wide by 9ft deep: with the spoil they erected a bank 4ft high and 12ft wide, on which they raised a parapet 4ft high made of stakes driven 2ft into the ground; which meant that the crest of the parapet was 17ft higher than the bottom of the ditch. A 2-yard running section of this fortification, requiring 324 cubic feet of excavation (12 cubic yards), could be completed by one man in thirty-two hours, or three days of work, or by twelve men in two or three hours.7 The legion which did the work could have completed its 14 miles of defences, involving 168,000 cubic yards of excavation, in 120 hours, or ten to fifteen days’ work.8

3. The Helvetians tried to cross the Rhône in the month of April. (The Roman calendar was then in great disorder; it was ahead by 80 days:9 thus 13 April corresponded to 23 January.) From then on the legions from Illyria had time to reach Lyon and the upper Saône, a journey which would have taken 50 days. Caesar defeated the Helvetians in battle twenty days after his crossing of the Saône: this battle therefore took place between 1 May and 15 May, corresponding to mid-August by the Roman calendar.

4. The Helvetians must have been courageous to have remained on the offensive for so long against a professional Roman army as large as their own. It is said that they took twenty days to cross the Saône, which would give a strange idea of their poor organization, but hardly seems credible.

5. The Helvetians numbered 130,000 on their return to Switzerland, but we should not conclude from this that their losses were 230,000 men, because many will have taken refuge and settled in Gaulish towns, and many others returned home later on. The number of their combatants was 90,000, amounting to one in four of the population, which seems a very high ratio. Some 30,000 from the canton of Zurich had been killed or taken at the passage of the Saône; thus they had at most 60,000 combatants at the battle. Caesar, with six legions and many auxiliaries, had the larger army.

6. The army of Ariovistus was no larger than that of Caesar. The number of Germans established in Franche-Comté was 120,000 men; but what a difference there must have been between armies formed as militias, consisting of all the men of a nation capable of bearing arms, and a Roman army composed of line troops who were professional soldiers and mostly unmarried. The Helvetians and the Suebi were without doubt brave: but what can bravery achieve against an army disciplined and organized like the Roman army? Thus there is nothing extraordinary about the successes achieved by Caesar during this campaign. However, this does not diminish the glory which he deserves.

7. The battle against Ariovistus took place in the month of September, in the neighbourhood of Belfort.

Chapter 2

Gallic War. Second campaign (57 BC)

I. War with the Belgians. Battle on the Aisne

The Belgians were of barbarian race. Their forefathers had crossed the Rhine, attracted by the beauty of the country. They had driven out the original inhabitants and settled there. They were reckoned to be the bravest of the Gauls: the Teutones and the Cimbri respected them and were afraid to offend them. The defeat of the Helvetians, the defeat of Ariovistus and the presence of the Roman army, which unusually was wintering in the Celtic region, aroused their resentment; they feared for their independence. After spending all winter in preparation, they took to the field in the spring with an army of 300,000 men commanded by Galba, King of Soissons, which supplied a contingent of 50,000 men. The people of Beauvais provided the same number, those of Hainault 50,000, of Artois 15,000, of Amiens 10,000, of Saint-Omer 25,000, of Brabant 9,000, of the Pays de Caux 10,000, of Vexin 10,000, of Namur 30,000, and lastly there were 40,000 Germans from Cologne, Liège and Luxembourg. The newcomers crossed the mountains into Caesar’s territory. Caesar raised two new legions and arrived with them at Sens during May (February by our calendar).

The peoples of the Celtic region remained loyal to him; those of Autun, Reims and Sens supplied him with an army, which he placed under the command of Divitiacus with orders to ravage the territory of Beauvais. Caesar encamped with his eight legions at Pont-à-Vaire on the Aisne in the territory of Reims. He established a bridgehead on the left bank, and enclosed his camp with a rampart 12ft high, in front of which was a ditch 18ft wide. The Belgian army was not slow to appear; it invested the little town of Bièvre, 8 miles from the Roman camp. This town had a garrison from Reims and was reinforced during the night, which the next day led Galba to march straight to Pont-à-Vaire. But finding the camp perfectly fortified, he took up a position 2 miles away. His forces occupied 7 miles of ground. After several days of skirmishes, Caesar marched out with six legions, leaving the two new ones to guard the camp. For fear of being outflanked, he built two lines of fortification, 600-800 yards long, perpendicular to the battle line; they were equipped with towers and machines. Galba wanted to bring matters to a conclusion with a battle, but he was hindered by the marsh which separated the two camps. He hoped the Romans would cross it, but they were too cautious. Each side retired to its camp at nightfall. Then Galba crossed the Aisne; during the night he attacked the defences on the left bank and started ravaging the territory of Reims, but with his cavalry and light troops Caesar drove him up the left bank of the Aisne. A few days later, the people of Beauvais learned that the people of Autun were at their frontiers and threatening their capital. They promptly broke camp and went to the aid of their country. This defection, once seen, was imitated; every man withdrew to his own country. Two days later, the Romans made a march of 24 miles and atta...

Table of contents

• Cover
• Title
• Copyright
• Dedication
• Contents
• Introduction
• Chapter 1 Gallic War. First campaign (58 BC)
• Chapter 2 Gallic War. Second campaign (57 BC)
• Chapter 3 Gallic War. Third campaign (56 BC)
• Chapter 4 Gallic War. Fourth campaign (55 BC)
• Chapter 5 Gallic War. Fifth campaign (54 BC)
• Chapter 6 Gallic War. Sixth campaign (53 BC)
• Chapter 7 Gallic War. Seventh campaign (52 BC)
• Chapter 8 Gallic War. Eighth campaign (50 BC)
• Chapter 9 Civil war. Italian campaign (49 BC)
• Chapter 10 Civil war. Spanish campaign (49 BC)
• Chapter 11 Civil war. Campaign in Thessaly (48 BC)
• Chapter 12 Civil war. Alexandrian campaign (47 BC)
• Chapter 13 Civil war. Illyrian campaign (47 BC)
• Chapter 14 Civil war. African campaign (46 BC)
• Chapter 15 Civil war. Spanish campaign (45 BC)
• Chapter 16 Death of Caesar (44 BC)
• Appendix Conventions adopted for the translation of measurements
• Notes