 He began preparing a campaign against Cyrus the Great of Persia.Before setting out, he turned to the Delphic oracle and the oracle of Amphiaraus to inquire whether he should pursue this campaign and whether he should also seek an alliance.The oracles answered, with typical ambiguity, that if Croesus attacked the Persians, he would destroy a great empire (ἢν στρατεύηται ἐπὶ Πέρσας, μεγάλην ἀρχὴν μιν καταλύσειν) – this would become one of the most famous oracular statements from Delphi.