When the persians retreated after their defeat at Salamis and Plataea, The Athenians returned to rebuild their city.
According to tradition, before the battle of Plataea, the greek city states had taken an oath never to rebuilt the temples distroyed by the persians in 480 Bc.
Conspicious among these buildings were sacred buildings of the Athenian acropolis.
THe sentiment of the Oath seemed irrelevant in the mid 5th century--> the persians were defeted an Athens had become a major power.
So Athens started to Rebuilding the Temples