The beginnings of the Christianization are also disputed in the historical texts: the Byzantine texts talk of duke Porin who started this at the incentive of emperor Heraclius (610–641), then of Duke Porga who mainly Christianized his people after the influence of missionaries from Rome, while the national tradition recalls Christianization during the rule of Dalmatian Duke Borna (810–821). It is possible that these are all renditions of the same ruler's name. The earliest known Croatian autographs from the 8th century are found in the Latin Gospel of Cividale.