Gaius Julius Caesar (13 July 100 - 15 March 44 BCE), Roman statesman, general, author, famous for the conquest of Gaul (modern France and Belgium) and his subsequent coup d'état. He changed the Roman republic into a monarchy and laid the foundations of a truly Mediterranean empire. In the following table, one can see the development of the army of Julius Caesar : when he became governor of Gallia Cisalpina and Gallia Narbonensis, he took charge of four already existing legions (numbered VII, VIII, IX and X), but during the campaigns in Gaul and in the Civil war against Pompey, the army grew. When Caesar was murdered, there were many more legions, which were taken over by Caesar's successors. Light red indicates a normal serving unit; dark red a veteran legion; grey means that it sides with Caesar's murderers; green and yellow indicate serving with Mark Antony or Octavian repectively. I A consular legion, recruited in 55, that was sent to Caesar during the crisis after the revolt of Ambiorix . He sent it back to the Senate in 50. I One of the four consular legions, recruited by Caesar when he was consul in 48. Marc Antony brought it to Dyrrhachium in the spring of 49. It became famous as the First Germanic legion . II One of the four consular legions, recruited by Caesar when he was consul in 48. It was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. In the summer of 44, it served under Marc Antony and was defeated at Modena, where it lost its standard (14 April 43). III One of the four consular legions, recruited by Caesar when he was consul in 48. It was present at Munda (17 March 45). In 42, it fought for the triumvirs at Philippi ; later, it participated in Marc Antony's war against the Parthian empire . As Third Gallic legion , it became famous. IIII One of the four consular legions, recruited by Caesar when he was consul in 48. It was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. In the summer of 44, it served under Marc Antony but it sided with Octavian and fought in the battle of Modena (April 43). In 42, it fought for the triumvirs at Philippi and returned to Italy with Octavian. Its later adventures are described here . V Alaudae One of the two new legions created during the war against Vercingetorix (52). It took part in Caesar's invasion of Italy (49) and stayed in Apulia for some time. In the winter of 49/48, it served at Dyrrhachium . It was not present at Pharsalus , but took part in the African campaign (46), where it gained its legionary emblem: an elephant. The Fifth was present at Munda (17 March 45) and sided with Marc Antony in 44. After the battle of Philippi (42), veterans were settled at Berytus . Later, it participated in Marc Antony's war against the Parthian empire . Its later adventures are described here . VI Ferrata One of the two new legions created during the war against Vercingetorix (52). In the summer of 49, it fought in Hispania in the battle of Ilerda. In the winter of 49/48, it served at Dyrrhachium . It was present at Pharsalus (9 August 48), Alexandria (48/47) and Zela (47). The Sixth was present at Munda (17 March 45). In 45, the veterans received land at Arles . The legion was reformed by Lepidus in the spring of 43. In 42, it fought for the triumvirs at Philippi ; later, it participated in Marc Antony's war against the Parthian empire . Its later adventures are described here . VII One of Caesar's four legions when he became governor of Gallia Cisalpina. He mentions it in his accounts of the battle against the Nervians , the two expeditions to Britain, and a campaign near Paris. The men were reenlisted in 53. During the civil war against Pompey, it fought in Hispania in the battle of Ilerda (summer 49). In the spring of 48, it served at Dyrrhachium . The Seventh was present at Pharsalus (9 August 48). After this battle, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. In 45, the veterans received land at Capua and Luca, but next year, when the dictator had been killed, many of them joined Octavian. In 42, it fought for the triumvirs at Philippi and returned to Italy with Octavian. Veterans were settled in Mauretania. Its later adventures are described here . VIII One of Caesar's four legions when he became governor of Gallia Cisalpina. He mentions it in his accounts of the battle against the Nervians and the siege of Gergovia. The men were reenlisted in 53. It took part in Caesar's invasion of Italy (49) and stayed in Apulia for some time. In the winter of 49/48, it served at Dyrrhachium . It was present at Pharsalus (9 August 48). After this battle, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. In 45, the veterans received land at Casilinum, but next year, when the dictator had been killed, many of them joined Octavian. In 42, it fought for the triumvirs at Philippi and returned to Italy with Octavian. Next year, the veterans received land near Teanum. Its later adventures are described here . VIIII One of Caesar's four legions when he became governor of Gallia Cisalpina. He mentions it in his accounts of the battle against the Nervians . The men were reenlisted in 53. During the civil war against Pompey, it fought in Hispania in the battle of Ilerda (Summer 49); later, the soldiers were transferred to Placentia, where they briefly revolted. In the spring of 48, it served at Dyrrhachium . It was present at Pharsalus (9 August 48). After this battle, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. Some veterans were settled in Picenum, others at Histria. Its later adventures are described here . X Equestris One of Caesar's four legions when he became governor of Gallia Cisalpina. He mentions it in his accounts of an encounter with the German leader Ariovistus (where he states that he has always trusted it completely), the battle against the Nervians (where the tenth legion saved the day), the invasion of Britain (where its standard bearer played a heroic role), and the siege of Gergovia. It is possible that the legion was called Equestris ("the knights") already, because Caesar describes how he used the soldiers as cavalry. The men were reenlisted in 53. In the civil war against Pompey, they fought in Hispania in the battle of Ilerda (summer 49). In the spring of 48, the Tenth served at Dyrrhachium . It was present at Pharsalus (9 August 48). After this battle, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. The Tenth was also present at Munda (17 March 45). In 45, the veterans received land at Narbonne . The legion was reconstituted by Lepidus in the spring of 43. In 42, it fought for the triumvirs at Philippi and veterans were settled at Patras; later, it participated in Marc Antony's war against the Parthian empire and the Actium campaign. When it had become part of the army of Octavian, the Tenth revolted and was punished: it lost its prestigious name. Veterans from other legions were added, and it became known as X Gemina ("the twin legion"). XI One of the two legions that Caesar recruited to fight against the Helvetians. He mentions it in his account of the battle against the Nervians (57). The men were reenlisted in 52. In the summer of 49, it fought in Hispania in the battle of Ilerda and in the spring of 48 at Dyrrhachium . It was present at Pharsalus (9 August 48), after which veterans were settled at Patras. The legion was disbanded in 45. In 42, however, it was reconstituted by Julius Caesar's heir Octavian. After it had fought for the triumvirs at Philippi , the legion may have participated in Marc Antony's war against the Parthian empire .Its later adventures are described here . XII One of the two legions that Caesar recruited to fight against the Helvetians. He mentions it in his account of the battle against the Nervians (57). The men were reenlisted in 52. During the civil war against Pompey, it took part in Caesar's invasion of Italy (49) and stayed in Apulia for some time. In the spring of 48, it served at Dyrrhachium . It was present at Pharsalus (9 August 48) and was called Paterna after the victory. In 45, the men were pensioned off and received land in the neighborhood of Parma (45). In 42, however, it fought for the triumvirs at Philippi , and later, it participated in Marc Antony's war against the Parthian empire . Its later adventures are described here . XIII One of the two legions that Caesar recruited to fight against the Belgians. He implies the existence of a thirteenth legion in his account of the battle against the Nervians , describes how it encountered the Aremoricans and states that it was present during the siege of Gergovia. The men were reenlisted in 51 and were with Caesar when he crossed the Rubico in January 49. After the conquest of Italy, they stayed in Apulia for some time. In the winter of 49/48, it served at Dyrrhachium . In late 48, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. They were probably also present during the battle of Munda (45); on their way back home, they were honorably dicharged and received land. The later adventures of the reconstituted unit are described here . XIV One of the two legions that Caesar recruited to fight against the Belgians. He implies the existence of a fourteenth legion in his account of the battle against the Nervians . The legion was destroyed by Ambiorix in the first weeks of 53 ( text ) and immediately reconstituted. During the civil war against Pompey, it fought in Hispania in the battle of Ilerda (49). In the spring of 48, it served at Dyrrhachium . It was not present at Pharsalus . In late 48, the soldiers were sent back to Italy to be pensioned off, but in 46, they participated in Caesar's African campaign. Its later adventures are described here . XV Constituted together with the reconstitution of the Fourteenth in 53. When Gaul was subdued, Caesar sent it to Italy to become part of an expeditionary force that was to be sent against the Parthian empire . However, the Senate used it to defend Italy against an attack by Caesar. When this took place in 49, the fifteenth sided with the invader. Caesar ordered this legion to occupy Africa, but it was annhilated in the autumn of 49/48.

XVI Constituted in January 49. Caesar ordered it to occupy Africa, but it was annhilated in the autumn of 49/48. After the battle of Philippi (42), survivors were settled at Troy . XVII One of the legions that Caesar constituted in the summer of 49. It may have seen action during the siege of Marseilles. XVIII One of the legions that Caesar constituted in the summer of 49. It may have seen action during the siege of Marseilles. XIX One of the legions that Caesar constituted in the summer of 49. It may have seen action during the siege of Marseilles. Veterans were settled Nuceria in 41. XX / XXIV Legions that Caesar constituted in the summer of 49. XXV One of the legions that Caesar constituted in the summer of 49. It participated in Caesar's African war (46). XXVI One of the legions that Caesar constituted in the summer of 49. It participated in Caesar's war in Africa (46), where it remained until 43. In 42, it fought for the triumvirs at Philippi . Next year, veterans received land near Luca. XXVII One of the legions that Caesar constituted in the summer of 49. In the winter of 49/48, it served at Dyrrhachium . It was present at Pharsalus (9 August 48) and Alexandria (48/47), where it stayed. It was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. It remained therefore in Egypt and seems to have sided with the republicans at the battle of Philippi (42). XXVIII One of the legions that Caesar constituted in the summer of 49; it fought in Hispania. It participated in Caesar's African war (46) and may have been present at Munda (45). In 42, it fought for the triumvirs at Philippi . XXIX One of the legions that Caesar constituted in the summer of 49. It may have been present in Hispania and participated in Caesar's African war (46). In 42, it fought for the triumvirs at Philippi . Next year, its veterans were settled near Hadria. XXX One of the legions that Caesar constituted in the summer of 49; it fought in Hispania. It participated in Caesar's African war (46). In 42, it fought for the triumvirs at Philippi . It was surnamed Classica ; settlers are attested in Beneventum. XXXI One of the legions that Caesar constituted in the first weeks of 48. Until 41, it served on Crete . It may have fought for Brutus and Cassius at Philippi. XXXII One of the legions that Caesar constituted in the first weeks of 48. It may have fought for Brutus and Cassius at Philippi. XXXIII One of the legions that Caesar constituted in the first weeks of 48. Veterans were settled in central Italy in 41. It may have fought for Brutus and Cassius at Philippi. XXXIV One of the legions that Caesar constituted after the defeat of Pompey out of his troops. XXXV One of the legions that Caesar constituted after the defeat of Pompey out of his troops. It was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. In the summer of 44, it served under Marc Antony and was defeated at Modena, where it lost its standard (14 April 43). XXXVI One of the legions that Caesar constituted after the defeat of Pompey out of his troops. It fought at Zela (2 August 47) and was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. It seems to have sided with the republicans at the battle of Philippi (42). XXXVII One of the legions that Caesar constituted after the defeat of Pompey out of his troops. It may have fought at Zela (47) and may have been surnamed Pontica . It was earmarked for Caesar's campaign against the Parthian empire , which was cancelled after the dictatator's death. XXXVIII Legions that Caesar constituted in 45 to substitute the veteran legions that were pensioned off. It fought on the side of the triumvirs during the battle of Philippi (42) and its veterans were settled in Macedonia . XXXIX / XXXXVII Legions that Caesar constituted in 45 to substitute the veteran legions that were pensioned off. Legion XXXXVI was surnamed Classica .