The Universal Synod of Ingelheim began on June 7, 948 in the then church of Saint Remigius in Ingelheim. Being summoned by Pope Agapetus II its primary goal was to resolve a long running Schism concerning the archiepiscopal see of Reims. The synod was presided by Marinus of Bomarzo, then the Roman Church's librarian. In the run up to the convocation there were two earlier synods, in Verdun in November 947 and in Mouzon in the beginning of 948, both considering the same problem but unable to resolve it.
Since 931 the archiepiscopal see was claimed by Hugh of Vermandois and Artald of Reims. Hugh was supported by his uncle, Hugh the Great while Artald was supported by both Louis IV. and Otto the Great. The aforementioned appeared at the synod in person while Hugh the Great was absent and not even substituted for. A clerk of Hugh of Vermandois named Sigbaldus then presented a letter stating that Guy, Bishop of Soissons, Hildegarius of Beauvais, Raoul [II] of Laon and the remaining bishops of the province of Reims had sent letters requesting Hugh be restored to the bishopric of Reims and Artald be expelled. Several of the bishops named stood up and protested they had not seen, nor heard, nor authorized such a letter. Sigbaldus was exiled and it was ruled that the see was to be given to Artald.
The following day Archbishop Robert of Trier stated that because the diocese of Reims had been restored to Artald, the synod should judge the one who invaded that see. The canons of holy law having been read, they decreed that Hugh of Vermandois was excommunicated and removed from the church "until he should do penance and make worthy satisfaction."