He famously refused to sign the 1937 Collective Letter in which the Spanish Church's hierarchy gave their support to Francisco Franco's forces,[1] and died in exile in Switzerland.

He was senator of the Spanish kingdom for the province of Tarragona from 1914 to 1916, and renounced the mitre of Cádiz to help calm the political and social tensions of Catalonia.

Following the Republican government's exile of Cardinal Pedro Segura y Sáenz, Vidal became the leading prelate of the Spanish Church.

He made fruitless attempts to mitigate the dispositions of the constitutional project which affected the rights of the Church, and to have the Vatican accept Luis Zulueta y Escolano as its Spanish ambassador.

The Francoist Minister the Conde de Jordana summoned the nuncio and passed to him a memorandum that declared the government wished, since part of the clergy "has been contaminated by separatist doctrines", for Enrique Pla y Deniel to be appointed to the See of Tarragona.

A liturgical rite for the reconciliation of Tarragona Cathedral—although it had not been burnt or destroyed, it was considered profane because of several acts of vandalism during the first days of the revolution—was carried out in a ritual officiated over by don José Artero, the canon of Salamanca Cathedral, in which he gave a "violent speech [that included a denunciation of] Catalan dogs!

Pius XII was outraged to hear that Franco desired to send Vidal, as a man hostile to the Francoist State, into exile.