Iznik is a city in Turkey which is known primarily as the site of the First and Second Councils of Nicaea, the first and seventh Ecumenical councils in the early history of the Christian church, the Nicene Creed, and as the capital city of the Empire of Nicaea (i.e. interim capital city of the Byzantine Empire between 1204 and 1261, following the Fourth Crusade in 1204, until the recapture of Constantinople by the Byzantines in 1261).