In the year prior to the start of the
Peloponnesian War (432 B.C.E.), Socrates
was in his late thirties and fought for Athens
at Potidaea. This city on the Chalcidic Peninsula, some 150 miles north of
Athens, was nominally an ally of
Athens. However, it maintained a magisterial
relationship with Corinth, an ally of Sparta. This made its loyalty suspect.
When Athens sought to test that loyalty by making certain demands, Potidaea refused. In the resulting siege and battle, Athens emerged victorious and Socrates distinguished himself in battle by saving the life of an associate, Alcibiades.