The decrees of the Plenary Council, with those of the Council of New York, were promulgated by him in a Synod held by him at New York, in September, 1868. The next year he was summoned to attend a General Council at Rome, the first held in the church since the Synod of Trent. The Council of the Vatican had been equalled by but few in the number of bishops, by none in the universality of the representation. Before modern science had facilitated modes of travel and communication, the area including those who attended was comparatively limited. To the Vatican Council, however, they came not from all parts of Europe only, but from Palestine, India and China; from the Moslem States of Africa; the European colonies; the negro kingdoms of the interior; America sent her bishops from Canada and the United States; the Spanish republics, Australia and the islands of the Pacific even had their bishops seated beside those of the most ancient Sees. Here Archbishop McCloskey was a conspicuous figure, respected for learning, experience, the firmness with which he held the opinion he mildly but conclusively advanced. In the committee on discipline his wisdom excited the highest admiration of the presiding cardinal. When the impious seizure of Rome made the sovereign Pontiff a prisoner in the Vatican, the proceedings of the council were deferred to better days, which the Church still prayfully awaits. Archbishop McCloskey returned to his diocese; but the malaria of the Campagna had affected his health, never rugged, and shattered some years previously by a railroad accident, on a journey required by his high office. But he resumed his accustomed duties, inspiring good works, or guiding and supporting them like the Catholic Protectory, the Catholic Union of New York, and its branch since developed to such wide-reaching influence, the Xavier Union. The impression which he had produced at Rome, from his early visit as a young priest to his dignified course in age as a Father of the Council of the Vatican, led to a new and singular honor, in which the whole country shared his honor. In the consistory held March 15, 1875, Pope Pius IX. created Archbishop McCloskey a Cardinal Priest of the Holy Roman Church, his title being that of Sancta Maria supra Minervam, the very church from which Rt. Rev. Dr. Concanen was taken to preside over the diocese of New York as its first bishop. The insignia of the high dignity soon reached the city borne by a member of the Pope's noble guard and a Papal Ablegate. The berretta was formerly presented to him in St. Patrick's Cathedral, April 22, 1875. According to usage he soon after visited Rome and took possession of the church from which he derived his title. He was summoned to the conclave held on the death of Pope Pius IX., but arrived only after the election of Pope Leo XIII., to whom he paid homage, receiving from his hands the Cardinal's hat, the last ceremonial connected with his appointment.