After the spartan king Lysander defeated Athenian fleet at the naval Battle of Aegospotami in 405 BC, the Athens finally lost the Peloponnesian War. Sparta became the undisputed major power among the Greek city-states. Stripped of its navy and its empire, Athens simply became just one more city under the political control of its more powerful neighbor in the south. This period in Greek history is called the Spartan hegemony, for although Sparta didn’t rule the city -states of Greece as if it were an empire, Sparta did exercise considerable influence over the domestic and foreign decisions of these independent states: it exercised, then, hegemonic control over these states.
Within capitulation of Athens Delian-Attic union were also fell. The Athenian hegemony was demolished. The Spartans had with their military campaigns impose their will to all Greeks. Sparta became the hegemonic and its hegemony maintained in Greece for 25 years.
Persians in the 400 BC invaded Asia Minor Greeks. The Spartans sent troops in order to support the army of Peloponnesian League.
The conflict was ended by Peace of Antalcidas, made by the Spartan envoy in 387 BC at the Persian Imperial Palace in Susa, between the Greeks and Persians. Peace of Antalcidas allowed for Spartans to make a deal with the Persians at the expense of other Greeks. Despite the provisions of the peace, the Greek cities in the Balkans and the Aegean Islands supported the old alliances and they were also founded a new alliances. Spartans tried to break that alliances in order to maintain hegemony.
The Athenians in the 378 BC established Second Athenian League in which accessed the many Greek cities. According to the program of Alliance, all allied cities were guaranteed freedom, autonomy and free choice of the internal political system. Almost all members of the former alliance had joined except the cities that were under the rule of the Persians. So there were found Greeks from almost all the Aegean and Ionian islands, the north coast of the Aegean and the eastern coast of the Ionian Sea and some others. The second Athenian alliance was established mainly for the defense of the Spartan hegemony. That created a new conflict between Athens and Sparta that lasted until the 371 BC when the Athenians concluded peace with the Spartans by which recognized the legality of the Athens and the Peloponnesian League. Opponents were largely reconciled by the fear of Thebes, that at that time was much strengthened.