Shortly after the election, the chapter petitioned the case to the Holy See to request Benedict's confirmation from Pope Gregory IX, who appointed John of Civitella on 25 February 1241 to conduct the procedure.

[1] After the disastrous Battle of Mohi in April 1241, Benedict fled together with king Béla IV and the royal court to the Dalmatian coast, and stayed there until the withdrawal of the Mongols from Hungary in 1242.

Udvardy argued Benedict's title meant a broad interpretation and merely Béla's wish, as the cathedral chapter was unable to meet under the chaotic conditions and a royal document issued in August 1242 states that there was sede vacante in the episcopal see of Kalocsa.

[7] The Archdiocese of Kalocsa suffered heavy damages due to the ravages of the Mongols, who left behind destroyed villages, depopulated regions, ruined churches and monasteries.

In addition, Benedict intended to acquire lands and estates for his archbishopric; he bought the half of the village Füzegy, near to Szond in Bács County (Vizić and Sonta in Serbia, respectively) from local lord Gregory Monoszló, who was forced to sell to the archdiocese because of its right of pre-emption in 1252.

Preparing for a new Mongol invasion, the Hungarian king abandoned the ancient royal prerogative to build and own castles, promoting the erection of new fortresses during his reign.

The pope sent a letter to Benedict to entrust him and his suffragan bishops by defining places to build castles in the territory of the archdiocese.

[8] When Béla IV filed a complaint that Zlaudus Ják was elected Bishop of Veszprém without his consent in 1245, which "contradicted the old customary law", Innocent instructed Benedict of Kalocsa to investigate the case in February 1245.

Simultaneously, Innocent granted Báncsa the privilege of returning to Esztergom, and continuing his administration of that diocese, until the next Feast of All Saints (November 1).

At that point he was to resign the Church of Esztergom to a prelate of the Kingdom of Hungary of his choice, and return to the Papal Curia by Christmas 1253.

Báncsa did not achieve his purpose, as the legitimacy of his administration was not recognized in Hungary; finally, the election of Benedict was confirmed by Pope Innocent on 25 February 1254.

[16] Benedict built a fortified manor and stone tower (also called archiepiscopal castle) at the northern tip of Margaret Island.

As a result, Béla IV resettled them to their old homes, and the archdiocese was granted the royal palace and the surrounding ancient castrum on 17 December 1256 (the phrase "Holy Crown" first appears in this donation letter).

Benedict held a national synod in Esztergom in the same year (1256), where several bishops and, among others, Blessed Eusebius, the First Provincial of the Order of Saint Paul the First Hermit (first mentioned in this capacity) attended, but its resolutions did not survive.

[17] Pope Alexander IV donated the privilege of annual 40-day indulgence to the visitors of the St. Adalbert Cathedral of Esztergom on the occasion of the Feast of Saints Peter and Paul in 1257.

The archdiocese lost a significant part of the royal income, due to privileges granted by the king to the conditional nobles.