During the period of Greek history from the last years of the Persian Wars till the beginning of the First Peloponnesian War, the primacy of Sparta declined whileAthens was gaining increased influence in Greece. The Athenian, Thucydides (460-400 BC), one among few contemporary historians, left behind the most creditable records about this period. Although he did not give enough documentation
for many events he described, his Histories remained the main resource of the facts from that time. In consideration of the fact that he was an Athenian and a participant of the Athenian army, future historians could not entirely count upon his writing.

In the 480-479 BC there was great anxiety about the strength and magnitude of the Persian threat. Although the Greeks had managed to force Persians retreat from the Greek mainland, the danger of reconquest by the Persians was still present. In the battle of Plataea (479 BC), the Greeks, under the Spartan regent and general
Pausanians, obliterated the Persian army. The Greeks also won a naval victory at
Mycale. Although the war drugged on for many years, these two victories marked the end of the Persian threat to Europe and the beginning of the period of Greek greatness.

The idea of panhellenism – the awareness of Greek unity- appeared as a reaction to the fear of the Persian invasion. This is how Persia helped the Greece to recognise their identity, which gave significance to the year 479 BC to be marked as the beginning of the Classical Greek period. At the other side, the year 479 BC does
not represent a vital turning-point in politics. Spartas control over her allies was still unbroken. After the Greeks triumph on Plataea, when the fear of the Persian invasion decreased, the idea of the united Greeks started diminishing. Phthonos (envy) was what characterised the relationship between Sparta and Athens,
and between many other city-states after the Persian Wars. Their rivalry was constant.
The most important direct result of the wars was the establishment of Athens as dominant Greek naval power. This gave Athens the opportunity to create, in the years to come, an extensive empire over the newly won territories which had no parallel in earlier Greek history. A new political order emerged among the Greek
states centred on the two great powers of Athens and Sparta that was to have a profound effect on later Greek history.
Soon after the end of the Persian Wars, the Athenians started rebuilding the walls around their city previously destroyed in the war. According to Thucydides, when Sparta heard about rebuilding, she immediately sent an embassy to the Athens
to ascertain the truth. Sparta maintained that no city-state should have the walls, for it could be dangerous in case of a new invasion. The possible invaders could use fortified cities as their military bases, as the Persians did during just finished war (I, 90-92). Thucydides was suspicious to Spartas reasons for disagreement about
fortification of Athens. Themistocoles, Athenian general, went to Sparta to silence their doubts. His plan was to hide the truth about the walls as long as Athenians finished them (I, 90). He even gave orders to the Athenians not to allow Spartas delegates to come back until the work of rebuilding the walls was done. When the walls were finally built he step out and confessed what Athenians have done,
informing Spartans that Athens was now able to make decision about her own interests and the interests of the rest of Hellos ( I, 91). As Thucydides stated, at this time Spartans were friendly disposed to Athens because of their gallantry in the Persian wars, so they did not openly manifest their anger (I, 92). He believed that
Sparta began to feel threatened because Athens was getting stronger and bigger.

The second reason of the strengthening of Athens was the Spartan commander, Pausanias. He commanded over the Hellenic forces against Cyprus and Byzantium. Pausanias was unpopular among his own people, especially in those states which were recently freed from Persian invasion. These states wanted Athens to take the command over from Sparta and to protect them from Pausanias. As there were some
indications that Pausanias co-operated with Persian king, Sparta did not have other choice but to pull him out of war and bring him up to the court. He was condemned to starve to death (I, 94-95). His arrogant and violent behaviour quickly led to dissatisfaction with Spartan leadership among the Greek allies. After this affair no
ally were ready to accept Spartas leadership in their descents. This is how Sparta decided to give up her leading position. In the words of Thucydides, they feared that when their officers went overseas they would become corrupted, as they had seen happen in the case of Pausanias, and at the same time they no longer wanted to be
burdened with the war against Persia. They regarded the Athenians as being perfectly capable of exercising the command and as being also at that time friendly to themselves (I, 95).

Spartas ongoing need to keep her army at home most of the time to guard against helots revolt also made prolonged overseas operations difficult to maintain. Athenians successfully took over the leadership and took in hand all important decisions about the war, quantity of money or number of ships that every country was
Difficulty of understanding these events stars with the question how good the relationship between Sparta and Athens really was after the Persian war. Thucudydes insisted that Sparta peacefully accepted Athens taking over of political power, citing the defensive speeches of Athens orators. But there is some evidence which direct
that Sparta was forced to accept the change. Herodotus (484?-425 BC) mentioned that Pausanians behaviour was only an excuse for Athens to take hegemony upon herself. The Athenians stripped the Lacedaemonians of their primacy (though nominally this was because of the arrogance of Pausanias (Herodotus 8.3-4). There was no indication that Sparta accepted that readily.

Secondly, Thucydides writings contain contradictions, although he clamed that Spartans gave away their authority willingly. Thucydides stated that in the 477/76 BC Sparta sent her army under the leadership of Pausanians on Cyprus and Byzantiuru (I, 96), which suggests that they had desire to extend their influence and stay in the race with Athens.

According to Diodorus, there was a disagreement between young and old Spartans about the issue of the hegemony. The younger Spartans wanted Sparta to keep their military leadership and involve her forces into naval expeditions while the older Spartans were against it. Some Spartans were ready to start a war with Athens,
instead of handing the leadership over to her. Hetoimaridas, an elder Spartan, managed to persuade the Spartans not go to war with Athens.

At that time in Tagea, an idea of launching Arcadian alliance and separating from the Peloponnesian League and Spartas leadership emerged. Arcadians along with Tagea tried to attain independence but Sparta managed, on two occasions (471 and 469 BC) to defeat and get them back into the Peloponnesian League.
The most important and dangerous for Sparta was increased restlessness of the serfs in Messenia and Laconia. After his failure outside of Laconia and the betrayal because of which Sparta abandoned him, Pausanians tried with the help of helots to throw off existing constitution of Sparta, but at the same time collaborating with
Persians. The ephors found out about it from Pausanianss own messenger, caught him into trap and repulsed the revolt.

In the 464 BC an earthquake struck Laconia. Sparta was seriously affected. More then 20000 people died. Helots tried to take advantage of the calamity, but Spartas king Archidamus re-established the control in Laconia. Problems with Messenia continued. With all the military help from other allies in the Peloponnese and Athens, Sparta did not succeed to capture Mount Ithome.
While Sparta was preoccupied with these developments, Athens availed herself of the hegemony. The fear of a renewed Persian invasion still existed. The states got together and in the 477 BC formed the Delian League, a giant military force under the
Athenians leadership. The League consisted of almost every state with a navy, no matter how small, including many of the Aegean islands and some of the Ionian city-states in Asia Minor. Spartas dominance and influence rapidly pared down.

Taking all the evidence into account, it can be said that Thucydides was not entirely right in his explanation of the change in control in Greece after the Persian wars. Sparta did not part with her authority willingly but was forced into it by Athens accession and other circumstances which prevented Spartas further expansion for some time.

Fornara, C.W. From Plataea to Potidaea (1979), Oxford, London
Herodotus, The History (1987), The University of Chicago Press, Chicago
Hornblower, S. The Greek World 479-323 BC (1983), Methuen, London
Meiggs, R. The Athenian Empire (1972), At The Clarendon Press,
Thucydides, The History – Book I (1979), Arno Press, New York