The Peloponnesian League, led by Sparta, defeated the Athenian league/empire.
Most of the Peloponnesian city-states.
Sparta .
We call it the Peloponnesian War today because it was between the Athenian Empire and the Peloponnesian League, of which Sparta was a member and leader. At the time, they referred to it the war between Sparta and its allies and Athens and its allies.
Sparta and its allies.
swords and spears
Alcibiades.
During the Peloponnesian war.
Athenians mostly were very good sailors and they had the strongest navy in Greece. During the Peloponnesian War, they defeated Sparta in countless ocean battles.
No, Sparta became most powerful after Athens was defeated in the Peloponnesian War, was stripped of its empire and revenue, and so lost its golden age without the money it mulcted from its empire.
The Athenian empire was stronger at sea, the alliance led by Sparta was stronger on land.
Notably , the main leaders during the Peloponnesian Wars was Pericles leading Athens and Archidamus II of Sparta ~ See related link below .
Athens was not in control of Sparta before, during or after the war. The only facet of its military that was stronger than Sparta's was the Athenian navy.