The siege of Orchomenes in 418 was a
short-lived success won by an alliance of Greek cities led by Argos and that
included Athens. In 421 the
Peace of Nicias had
temporarily ended the fighting during the Great Peloponnesian War.
One of Sparta's reasons for agreeing to the peace was that their peace
treaty with Argos, a key rival in the Peloponnese, was about to expire and
Sparta didn't want a war on two fronts.
The peace of Nicias was unpopular in Corinth, another of Sparta's allies. The
Corinthians convinced the Argives to form a new defensive alliance, aimed at
reducing the power of Sparta in the Peloponnese. Over the next two years this
new alliance evolved until by 418 it included Athens, Mantinea and the Eleans,
as well as Argos. Ironically Sparta could still call on Corinth, where
enthusiasm for the new alliance had quickly faded.
The Boeotians also remained loyal, despite having briefly dallied with the
Argive alliance. In the summer of 418 the Argives attacked the Epidaurians in
Arcadia. The Spartans moved to defend their allies, and summoned their own
allies. Argos also summoned their allies, and a battle seemed inevitable.
Instead, as the two armies faced each other outside the city of Argos their
leaders agreed not to fight. The Spartans then pulled back across their
borders. Soon after this the Athenians arrived, and convinced their allies to
keep fighting. Their first move was to attack the city of Orchomenos in
Arcadia, where the Spartans were holding some hostages. The allied army arrived
outside the city, besieged it, and carried out a number of unsuccessful
assaults on the place. Despite these failures, the defenders were worried.
Their defences were weak and their allies weren't close enough to arrive in
time. They decided to surrender on terms - they were to change sides, join the
Argive alliance, free the Spartan hostages and provide hostages of their own.
After the surrender of Orchomenos the allies decided to attack Tegea, a key
Spartan ally. They moved to Mantinea to prepare for the attack, but instead
suffered a heavy defeat at the hands of the Spartans at the battle of