Council of Ephesus
The primary causes of the schism were disputes over conflicting claims of jurisdiction, in particular over [[papal supremacy|papal authority]]—[[Pope Leo IX]] claimed he held authority over the four Eastern patriarchs – and over the insertion of the [[Filioque clause]] into the [[Nicene Creed]] by the Western patriarch in 1014. The seventh canon of the [[First Council of Ephesus|Council of Ephesus]] declared: