After continually pushing Pompey out of Italy, Julius Caesar had to move his plans on the enemy’s territory, Greece and Macedonia. Knowing that Pompey had a number advantage, he was ready for every risk. The first problem was to move about 40.000 soldiers to the Apennine Peninsula. It had a well-protected shore with a powerful fleet of Pompey. Caesar decided to transport his troops in three waves.
The first consisted of Caesar and 15.000 legionaries. The second Mark Antony with 20.000 soldiers. The rest came in the third. The transfer turned out to be difficult, and it caused a loss of soldiers and transporters. After gathering the whole army on the Peloponnesian Peninsula, Caesar marched on Pompey. They had a lot of convenient places to finish the war, but both of them were scared to make the first move. Eventually, after small cavalry encounters and auxiliary units, both armies faced each other in battle formations. The battle was inevitable. The only thing that scared Pompey was the expert infantry of Caesar. He knew that he could count only on the cavalry.
As a result of casualties from the transport and the encounters, Caesar lost a big part of his army, which was the cause of less numerous force. Another reason was refusing obedience of soldiers who switched sides and joined Pompey’ army.
The primary Caesar forces were 22.000 soldiers (nine depleted legions), from 5.000 up to 10.000 auxiliary troops and 1.800 of cavalry. It’s worth mentioning that most of Caesar’s legions were Spanish, they were recruited in the are of Iberian Peninsula. Spanish legionaries were in favour of an excellent reputation. It is considered that they were the best troops in the Roman empire. Caesar’s cavalry consisted of Spanish and 300 german riders who he recruited during the Gallic Wars. Sometimes they were his guard because Germans had the best horses and the best-trained riders.
It’s hard to determine Pompey’ forces. Initially, he had 40.000 soldiers. Then with new volunteers and integrating a part of Caesar’s troops, Pompey gad a significant advantage over the rival. It’s evaluated that he had from 40.000 up to 60.000 (twelve legions), 4.200 auxiliary troops, and from 5.000 up to 7.000 horse riders. Titus Labienus led the cavalry. He was Caesar’s general during the Gallic Wars, but he joined Pompey at the start of the civil war. Labienus brought 1.000 German and Gaul riders to Pompey’s army. Pompey’ huge advantage could give him victory, but Caesar’s infantry once again saved his life.
Data on the numbers go on Caesar’s memories, and some historians think the disparities between both armies were smaller.
The tenth legion was positioned on the right flank of Caesar’s army because it was the most combative one. It was supposed to be supported by 1.000 riders and auxiliary troops. General Sulla led the right side of the army. In the centre, the commander was Domitius Calvinus leading the Spanish legions. The leader of the left flank, where the famous ninth legion stood, was Mark Antonius. Caesar got off his horse and joined the tenth legion on the right flank. He briefed his soldiers not to throw javelins but to use them to pierce through riders. Now Caesar was waiting on the first move of Pompey.
Pompey entrusted Labienus with 7.000 riders on the left flank. Lucius Ahenobarbus led infantry. The first legion supported cavalry, which was further on the left. Metellus Scipio was commanding the centre, and Lucius Lentulus controlled the right side. Pompey planned to crush Caesar’s cavalry with his own and pull out Caesar’s best legion and destroy it. The plan didn’t work out.
On the ninth of August 48 BCE, the fate of Rome was to be decided.
Pompey marched out with his units and set them in the traditional battle position on the plain between the camps. Caesar knew about the advantage of the enemy’s cavalry, so he set his soldiers in three rows. To defend the behind, he sectioned from six to eight cohorts off (about 2.000 men) placed on the back of his right-wing (the fourth row) and extended spaces between his cohorts, so the length of his lines matched the range of enemies’ lines. The third line of primary forces was supposed to be the reserve for the first two.
Labienus charged first with his riders. After fast trot, he found himself near Caesar’s army. Then Caesar sent his cavalry with Sulla as the commander. Initially, none of the troops was leading; however, Sulla’s force started to thin and retreat. When the tenth legion had exposed right side Labienus instigate to the second part of the plan – to pull out the best legion of Caesar which, after the attack of riders, didn’t push them. They stood still and stroke horse riders with their javelins. Labienus’ charge exposed his right flank, which was attacked by infantry and the rest of cavalry from the fourth row led by Julius Caesar himself.
Pompey cavalry was thinning out in frightening speed, which caused it to flee. Labienus wasn’t able to call them back, so he fled with them. Then Caesar proceeded to his plan. He moved infantry and briefed them to throw the javelins and clash the enemy lines. Onrushing Caesar’s infantry cut through less experienced Pompey’s legions. Additionally, the tenth legion, infantry, and cavalry got on the enemy’s back, which could already be counted as a victory. Pompey’s infantry started to flee; therefore, it was massacred by the chasing legionaries. Catching them up in the camp, Caesar gave them an alternative. He promised not to punish them if they join Caesar’s victorious army. On his offer, soldiers joined him with relief.
After losing battle, Pompey immediately escaped to allied Egypt, where he wanted to rebuild his army and lead the rest of the legions.
But he wasn’t able to bring the plan into play because right after going ashore, he was murdered on the order of young pharaoh Ptolemy XIII, and his head was sent to Caesar as a gift. Ptolemy, who was just a kid, did it being influenced by regents. He wanted to gain Caesar’s favour, hearing about his kindness (Caesar guaranteed amnesty to many opposing senators and allowing his enemies to come back to the capital and regain their lost positions).
Death of the rival in such circumstances enraged Ceasar more than it joyed him. However, the end of his main opponent in the empire meant a more straightforward way to (practically) monocracy. Caesar lost rival for the throne, but Pompey had two sons Gnaeus and Sextus, supported by Metellus Scipio and Cato.