Final answer:
The Council of Trent was a major ecclesiastical assembly that convened over 18 years to address the challenges of the Protestant Reformation, resulting in significant doctrinal reaffirmations. Although the exact number of archbishops and bishops involved is not provided in the given information, the council's sessions were attended by many high-ranking Church officials.
Step-by-step explanation:
The Council of Trent was a pivotal series of meetings in the history of the Catholic Church, which involved a significant number of church hierarchy, including archbishops and bishops, to address the issues raised by the Protestant Reformation. The council had a total of 25 sessions over a span of 18 years, beginning in 1545. The proceedings included discussions on various Church doctrines and the role of religious art, leading to reaffirmations of Church teachings and the establishment of measures against the Protestant principles of the Reformation.
Specifically, the Council affirmed the Doctrine of Merit, the existence of Purgatory, the importance of all seven sacraments, the necessity of religious art, and the authority of the Church's scripture, teachings, and traditions. However, the documentation available does not provide a definitive number of archbishops and bishops involved in the Council of Trent. The records from that period, such as the Session of the Council of Trent documented in Matthias Burglechner's "Tyrolischer Adler", could give a better insight into the exact participation figures.