In 407 B.C. and again in 405 B.C.. the Spartans in alliance with their old enemies, the Persians, destroyed two Athenian Fleets.
Although Athens had suffered defeats before, notably in Sicily in 415 B.C., they had always managed to rally and beat back the Spartans. This time, however, Athens could not make up the losses.
The Spartan fleet soon took control of the mouth of the Dardanelles which stopped Athens’ grain supply.
In February 404 B.C., the Spartan fleet blockaded the Athenian port of Piraeus. The city was subjected to three months of starvation until Athens surrendered in April.
The Spartans exacted harsh terms from the defeated Athenians. They demanded that the city walls be torn down, that the Athenian fleet be handed over, that exiles be allowed to return, and that Athens should forthwith become an ally of Sparta.