It is highly probable that during the period from 479 to 447 BC, the Acropolis was in a state of ruin. According to historical records, before the battle of Platea, the Greeks had sworn not to restore the sacred buildings that the Persians had destroyed. Plutarch reports that in 450 B.C., Pericles called an assembly for the purpose of suggesting to the Greeks that they break this oath. However, some writers such as Theopompus questioned the very existence of such an oath.