chapter. This dissension was a chapter of a wider conflict between the partisans of Emeric and his rebellious brother Duke Andrew. John was mentioned as bishop in 1199 too, when Emeric transferred the right of patronage of Dénesmonostora (lit. "Denis' monastery") within the gens Becsegergely. The family monastery located at the border of the dioceses of Csanád and Várad. When Emeric prepared a crusade under the pressure of Innocent in the spring of 1201, the pope sent a letter to Duke Andrew, Saul Győr, Archbishop of Kalocsa and John to "put aside the hostility and keep the peace of the realm" (i.e. govern the kingdom under the king's absence). Innocent's instruction reflects John's growing political influence during the last regnal years of Emeric. Archbishop of Kalocsa The elderly Saul Győr of Kalocsa died either in 1201 or 1202. He was succeeded by John, who was considered the king's loyal supporter by then. In the same time, Emeric invaded Serbia and helped Stephen Nemanjić's brother Vukan seize the throne, while Emeric himself adopted the title of King of Serbia. This act has increased the ecclesiastical significance of the Archdiocese of Kalocsa, which located along the southern border of the Hungarian kingdom. Pope Innocent had urged the king to take measures to liquidate the Bosnian Church (often called Bogomils or Patarenes), whom the Catholic Church considered to be heretics. To avert the Hungarian attack, Ban Kulin of Bosnia held a public assembly on 8 April 1203 and affirmed his loyalty to Rome in the presence of papal legate John de Casamaris, while the faithful abjured their mistakes and committed to following the Roman Catholic doctrine. Following that King Emeric and Archbishop John held talks with Ban Kulin's unidentified son, the "heretic" envoys (priests Ljubin and Dragota) and the papal representative at Csepel Island. On 30 April, the envoys and Kulin's son confirmed their oath of allegiance before John and Kalán Bár-Kalán. In the same time, John participated in the intention of prepare the church union between the Serbian Church (then still subordinated to the Ecumenical Patriarchate of Constantinople) and the Roman Catholic Church. After Emeric's successful military campaign, Pope Innocent assigned the territory of Serbia as a suffragan diocese to the Archbishopric of Kalocsa. On 22 March 1203, the pope appointed John as the papal representative of the issue and sent to the court of the Hungarian vassal Vukan, Grand Prince of