The extent of the historical basis of the Iliad has been a topic of scholarly debate for centuries. While researchers of the 18th century had largely rejected the story of the Trojan War as fable, the discoveries made by Heinrich Schliemann at Hisarlik reopened the question in modern terms, and the subsequent excavation of Troy VIIa and the discovery of the toponym "Wilusa" in Hittite correspondence has made it plausible that the Trojan War cycle was at least remotely based on a historical conflict of the 12th century BC, even if the poems of Homer are removed from the event by more than four centuries of oral tradition.