In 398 BCE, the city-state of Syracuse launched a invasion of Himera, provoked by the Athenian Allies expansion in the area. The Tyrant of Syracuse ordered the invasion in early spring, and positioned his far relative, Alextrus, the commander of the force. Alextrus initially divided his forces into two, a scouting force of 3,000 and the main force of 12,000. The smaller force marched westward, in a effort to make a defensive line against the Athenians while the main force marched on Himera.
The Himerans mobilized quickly as well, and assigned a local noble, Paenus, to lead their forces to battle against the invading armies. Paenus was well aware of his numerical inferiority, and chose his position near the Greek town of Capilium, on a large hill that provided Paenus with cover. When Alextrus arrived, he burned Capilium to the ground, and marched upon Paenus without hesitation, inciting fear within the Himeran lines.
All data gathered from the battle is from the writings of a Greek Historian, Pelnen, who argued that the Syracuse forces relied on their superior numbers, while sympatheticly defining the Himeran armies chances of victory as, "minimal". Pelnen describes the battle:
"The Southern Sicilians marched in good order up the hill side with a barrage of arrows raining down on them, though some Syracusian warriors fled, bringing great concern to the general Alextrus who discovered wide gaps in his line. He ordered his troops to march extremely close by one another, with their shields carefully positioned over their heads. Paenus was able to exploit this weakness though, and charged his army down the hill, catching the Syracusian's in a far from perfect position. The phalanx shattered, and the Himerians continued to push, but Alextrus was able to swing his reserve infantry up the hill, and entrap the Himerian army. After bitter fighting, the Himerians made a breakthrough on the right side, but fled the field of battle as few greeks had remained. Paenus insisted they continue to fight, but with pressure on all sides, he left the field and returned to his home.
In truth, the Battle of Capilium provided much more to Syracuse then Ancient Historians argued, with a series of supply routes, roads, and pathways to Himera itself in enemy control. Alextrus was praised as a great hero after the battle, but was not content with his victory, and decided to continue his campaign, marching on Himera.