Final answer:
Charles Borromeo, the Archbishop of Milan, was instrumental in implementing the decrees of the Council of Trent, founding seminaries, and tending to the needs of his diocese during the plague.
Step-by-step explanation:
The question appears to be somewhat misplaced because it refers to Charles Borromeo, who was actually the Archbishop of Milan in the 16th century, but provides details about English monarchs and church-state relations which are not directly related to Borromeo's actions. Therefore, a correction is needed to properly address the actions relevant to Charles Borromeo.
Saint Charles Borromeo was a cardinal and the Archbishop of Milan, recognized for his significant contributions to the Catholic Reformation. He was a leading figure in the final sessions of the Council of Trent and was diligent in implementing the council's reforms within his diocese. He founded seminaries for the education of priests, enforced the decrees of the council, and personally tended to spiritual and material needs of his flock, including during the plague that struck Milan in 1576-1577. His efforts greatly influenced other church reforms across Europe.