The battle of Amphipolis (422 BC) was a disastrous Athenian defeat in Thrace, inflicted on them by an army led by the Spartan Brasidas (Great Peloponnesian War). Both Brasidas and the Athenian commander Cleon were killed in the battle, and their deaths helped to pave the way to the short lived peace of Nicias (421 BC).
The city of Amphipolis was located in the north-east of Greece. It was built where the River Strymon emerged from Lake Cercinitis, and was about three miles from the sea. In 422 BC it was a new settlement. The area was contested with the Thracians, and two earlier attempts to create a city at the site had failed - the first in 497 BC and the first Athenian attempt in 465 BC. This second colony had been destroyed by the Thracians and the inhabitants massacred, but despite this setback the Athenians persevered, and the successful colony was founded in 437 BC.
The city had not been founded for long when the Great Peloponnesian War broke out. At first the fighting didn't directly affect the city, but this changed after the Spartan commander Brasidas led an army overland to Thrace. In the winter of the eighth year of the war (424-423 BC) Brasidas captured the city. A relief expedition led by the future historian Thucydides only just failed to arrive in time, although did prevent the fall of the port of Eion. Thucydides was exiled for his part in the fall of Amphipolis.
In the following spring the Athenians and Spartans agreed a one year truce, which was successfully observed, expiring in the summer of 422 BC. Brasidas remained in Thrace during this period, campaigning in areas not covered by the truce.
After the truce expired the Athenian politician Cleon lead an army of 1,200 hoplites and 300 cavalry supported by a larger contingent of allied troops into Thrace in an attempt to restore Athenian control of the area. After an early success at Torone, Cleon then sailed along the coast towards Amphipolis. He reached the port of Eion, three miles from the city, and then waited for reinforcements to arrive.
Brasidas also moved to the area, and took up a position on Cerdylium, on high ground close to Amphipolis and with a good view of the Athenian position. Brasidas expected Cleon to advance towards Amphipolis without waiting for reinforcements, and hoped to have a chance to attack the Athenians while they were still comparatively weak. Brasidas had 2,000 hoplites, 300 Greek cavalry, 1,000 local peltasts, the army of Edon and 1,500 Thracian mercenaries, so perhaps outnumbered Cleon although the quality of his troops wasn't as high.
Cleon wasn't a popular commander, and he didn't have the full support of his troops. He was unable to convince them of the wisdom of waiting for reinforcements, and was forced to make some sort of move to keep them content. He decided to march up the river to Amphipolis to examine the city and its defences. When Cleon made his move, Brasidas abandoned his watching position and moved into the city, but he kept his troops hidden.
Brasidas was aware of the inferior quality of his troops, and decided to try an unusual tactic. The Athenians were somewhat disorganised outside the city. Brasidas decided to lead 150 his best men in a surprise attack on the Athenian centre. Once this advance guard was fully engaged, his second in command Clearidas was to attack with the rest of the army. Brasidas hoped that the Athenians would be distracted by his own attack and demoralised when a second army appeared.
Outside the city the Athenians were increasingly aware of movement behind the gates. Cleon decided to order his army to withdraw back to the coast to wait for reinforcements before risking a battle. The left wing of the Athenian army moved first. The right wing, with Cleon in personal command, then began to wheel around towards the centre to join the retreat. During this movement their shields, which were held on the left, were thus facing away from the gates of Amphipolis.
Brasidas realised that this was the moment to attack. He led his 150 men out of city using a minor gate, and attacked the Athenian centre, which quickly collapsed. Brasidas then turned on the Athenian right, while Clearidas brought the rest of the army out of the city and joined the battle. Seeing the disaster that was befalling the rest of the army the Athenian left, which was already some way down the river, fled, leaving the right to fight alone.
The fighting on the Athenian right wing cost both commanders their lives. Brasidas was mortally wounded during his attack on the right wing. He was taken from the battlefield and survived for long enough to learn of his victory. He was later buried in Amphipolis, where he was later commemorated as the founder of the city. Thuycidides, who was always rather hostile to Cleon, records his death in less flattering terms. Seeing that the battle was lost, he fled from the battlefield and was killed by a Myrcinian peltast.
The Athenian right attempted to make a stand on a nearby hill. They were able to fight off two or three attacks by Clearidas and his hoplites. They were less successful when Clearidas surrounded them with light troops, cavalry and peltasts, who pelted them with missile weapons. Under this bombardment the Athenian right also broke and fled. The survivors of the disaster reached safety at Eion, but 600 Athenians had died during the battle. According to Thucydides the Spartans and their allies only lost seven men.
The most significant result of the battle of Amphipolis was the death of both Brasidas and Cleon, two of the more warlike leaders. With both men removed from the scene the peace negotiations that had been going on since the Spartan defeat at Sphacteria were successful, and in the following year the Peace of Nicias temporarily ended the fighting.