The Editors of Encyclopædia Britannica, Sergius II "A story that Pope Sergius IV (1009–1012) sent Sergius II, a letter insisting on the Latin Trinitarian teaching that the Holy Spirit relates to both Father and Son (Filioque), thus initiating the Eastern schism when Patriarch Sergius II reacted by erasing the Pope's name from the Byzantine prayer intercessions, is the invention of 12th-century controversialists".
