In 222 BCE, the Battle of Sellasia was fought between the Macedonians under Antigonus III against the Spartans under Cleomenes III during the Cleomenean War.
Why did it happen?Â
In 235 BCE, Cleomenes III became king of Sparta after deposing his father, Leonidas II. An ambitious ruler, Cleomenes sought to restore traditional Spartan discipline and weaken the influence of the ephors (Sparta’s elected officials). In 228 BCE, the Achaean League declared war on Sparta after Cleomenes constructed a fort near Megalopolis, which was disputed land between both sides. At first, Cleomenes scored several notable victories over the Achaean League, defeating them in battle at Mount Lycaeum (227 BCE) and Dyme (226 BCE). In the face of Sparta’s superior military, the Achaean League allied with the Macedonian king, Antigonus III, who invaded the Peloponnese in 224 BCE. Subsequently, Cleomenes withdrew from the Isthmus, and Antigonus occupied several important towns, such as Argos, Tegea and Mantinea. By 222 BCE, Cleomenes was left isolated in the valley of Laconia, and after his forces had sacked Megalopolis the previous year, the Macedonians and Achaean League marched south to confront him at Sellasia.
Who was involved?Â
The Macedonian army at Sellasia numbered 28,000 infantry and 1,200 cavalry. The Macedonian army was arrayed in three divisions. On the left wing were 10,000 phalangists and 3,000 peltasts under Antigonus III. In the centre, 1,200 cavalry and 8,000 peltasts were commanded by Philopoemen, while on the right wing were stationed 7,000 phalangists and peltasts under Demetrius of Pharos. The Spartan army at Sellasia consisted of 20,000 infantry and 650 cavalry. Like the Macedonian army, the Spartan army was arrayed in three divisions. The left wing consisted of 5,000 phalangists under Eucleidas, the centre comprised 9,000 peltasts and 650 cavalry, and on the right wing were positioned 6,000 phalangists under Cleomenes III himself. The Spartan left and right wings were stationed on the Eva and Olympus Hills.
What happened?Â
The Macedonian right wing began the battle by attacking the Spartan left wing on Eva Hill and forcing it downhill. In response, the Spartan peltasts stationed in the Oenus Valley attacked the Macedonian right wing in the flank and rear. After disregarding orders from his superior officers, Philopoemen led the Macedonian cavalry against the Spartan peltasts and cavalry, which caused them to retreat to their original positions. As the Macedonian right wing reorganised, the Spartan left wing under Eucleidas counterattacked but became disorganised by rough terrain and was defeated. At the same time, Philopoemen led a second cavalry charge against the Spartan cavalry. Upon seeing the defeat of his left wing and cavalry, Cleomenes III abandoned his defensive position on Olympus Hill and attacked the Macedonian phalanx under Antigonus III but was defeated and fled the battlefield. Spartan casualties at Sellasia numbered 5,800 killed.
What changed as a result?Â
The Battle of Sellasia was a decisive Macedonian victory. In the aftermath of the battle, Cleomenes fled to Egypt while Antigonus occupied Sparta, which he treated courteously and allowed the Spartans to keep their laws and policies. Antigonus left Sparta after a few days to confront the Illyrians in Macedonia and died in battle the following year. Meanwhile, in Egypt, Cleomenes stayed at the court of King Ptolemy III in Alexandria, who gave the exiled Spartan king a yearly pension and promised to provide ships and money to help him regain the Spartan throne. However, when Ptolemy III died in 221 BCE, he was succeeded by Ptolemy IV, who neglected his duties, indulged in wine and concubines, and placed Cleomenes under house arrest. In 219 BCE, Cleomenes escaped house arrest and attempted to incite a revolt against Ptolemy IV, but when this failed, he committed suicide.
Bibliography
Bennett, Bob. & Roberts, Mike. Twilight of the Hellenistic World. Barnsley, Pen & Sword Military, 2012.
Holmes, Richard. & Marix Evans, Martin. A Guide to Battles: Decisive Conflicts in History. Oxford, Oxford University Press, 2009.
Plutarch. Life of Cleomenes. Translated by Bernadotte Perrin. Cambridge, Loeb Classical Library, 1921.
Polybius. Histories. Translated by Evelyn S. Shuckburgh. New York, Macmillan, 1889.