While the Parthenon was the most impressive temple on the Acropolis, another building, the Erechtheion was built to accommodate the religious rituals that the old temple housed. Construction of the Erechtheion began in 420 while the Peloponnesian war was interrupted by the Peace of Nikias and continued through some of the most difficult times for the Athenians at war. During this time the Athenians suffered a devastating defeat at Syracuse, saw their empire unravel through consecutive revolts, had their cherished democracy replaced by a brief oligarchy, and endured major defeat. The Erechtheion construction was concluded in 406 BCE, and soon thereafter, in 403 BCE Athens fell to the Spartans.