Hungarian historian Antal Pór considered that he is identical with that namesake provost of Opole, who functioned as rector of the ultramontanes at the University of Padua in May 1308.

[2] Polish historian Stanisław Sroka called Pór's argument as hypothesis, but agreed, Bolesław may have been a student of an universitas in Italy, taking into account his Italian language skills and later diplomatic missions to the peninsula.

At the end of 1320, Bolesław went to the Kraków court, and at the beginning of the next year (1321) the King Charles I gave him the most important and powerful position of the Hungarian church: the Archbishopric of Esztergom.

These countries (who had a long-lasting dispute over the Adriatic coast), finally entered into an agreement after the Archbishop's mediation, who visited the republic in the spring of that year: the rich cities of Dalmatia (who included Zadar and Split) were placed under Hungarian rule.

However the recovery of Nezsider (today Neusiedl am See, Austria) was unsuccessful, despite even Pope John's intervention, as the donation letters were lost and Bolesław could not prove that the archdiocese was granted the land by King Andrew III's consort Queen Agnes.

He bought Csév, Esztergom County for inexpensive 50 silver denari from Mikóca Rosd, who, with that step, paid his debts, which existed since his act of unintentional homicide against a serf in Kesztölc, a subject of the archdiocese.

[9] During the first six years of his rule as Archbishop (1321–1326), Bolesław had to fight against an extreme Franciscan faction, the Fraticelli, who at that time were considered too radical by Pope John XXII.

[6] When Pope John called the Hungarian Benedictine abbots to convene their collegiate annually in order to restore discipline, he simultaneously commissioned metropolitans Bolesław and Ladislaus Jánki to supervise the enforcement of the provision.

Its bishop Nanker complained to the Holy See in 1324 that archbishops Thomas and his successor Bolesław have exercised unjustifiably ecclesiastical authority over the Catholic communities of Podolin, Gnézda and Lubló (present-day Podolínec, Hniezdne and Stará Ľubovňa in Slovakia, respectively).

This conflict was only resolved in 1332, when Bartholomew's successor Prot ruled in favour of Kraków, however the towns passed in the reign of Hungary in later in the second half of the 14th century, overwriting the verdict.

[6] The clergyman reported on 1 May 1328 that immediately after the death of their bishop John, they sent a delegation to King Charles, but their envoys were captured en route and imprisoned in Esztergom Castle by Bolesław's troops.

The full support shown to the Piast princes by King Charles and Queen Elizabeth ended that dispute with a complete success to Mieszko.