By the time Emperor Lebna Dengel and the Portuguese had established diplomatic contact with each other in 1520, Prester John was the name by which Europeans knew the Emperor of Ethiopia. The Ethiopians, though, had never called their emperor that. When ambassadors from Emperor Zara Yaqob attended the Council of Florence in 1441, they were confused when council prelates insisted on referring to their monarch as Prester John. They tried to explain that nowhere in Zara Yaqob's list of regnal names did that title occur. However, their admonitions did little to stop Europeans from calling the King of Ethiopia Prester John. Some writers who used the title did understand it was not an indigenous honorific; for instance Jordanus seems to use it simply because his readers would have been familiar with it, not because he thought it authentic.