The right exercised by Byzantine emperors and Holy Roman Emperors to confirm the election of a Pope, which was last exercised in the Early Middle Ages, appears unrelated to the Early modern legal claim of jus exclusivae by the Holy Roman Empire, France, and Spain. Pope Pius IV, in his bull In Elgidendis, excluded formal support of the Church to such rights and external interventions in the conclave. It was explicetely forbidden in 1904 with the bull Commissum Nobis of Pope Pius X In the 17th century, treatises in defence of this right first appear. It was notably invoked in 1644 by both Spain and France. Spain used it to exclude the election of Giulio Cesare Sacchetti, whereas France failed to veto the election of Giovanni Battista Pamphili.
The right has never been formally recognized by the papacy, though conclaves have considered it expedient to recognize secular objections to certain papabili, that is, candidates for the papacy, and to accept secular interference as an unavoidable abuse. By the papal bullIn eligendis of 9 October 1562 Pope Pius IV ordered the cardinals to elect a pope without deference to any secular power. The bull Aeterni Patris Filius forbids cardinals to conspire to exclude any candidate. These pronouncements however, did not specifically condemn the jus exclusivae. In the apostolic constitution In hac sublimi of 23 August 1871 Pope Pius IX forbade any kind of secular interference in papal elections. The most recent attempt to exercise the right to excludeCardinal Rampolla in 1903 was rejected by the conclave, although over the course of several ballots Rampolla, who had been the leading candidate, lost support until the conclave elected Cardinal Sarto, Saint Pius X. The following year, Pius X forbade the jus exclusivae in the apostolic constitution Commissum Nobis of 20 January 1904: Since then the cardinals in conclave have been enjoined to take this oath: "We shall never in any way accept, under any pretext, from any civil power whatever, the office of proposing a veto of exclusion even under the form of a mere desire… and we shall never lend favour to any intervention, or intercession, or any other method whatever, by which the lay powers of any grade or order may wish to interfere in the election of a pontiff." No power has openly attempted to exercise the right since 1903. France had become a republic in 1870. After World War I, there was no German Empire and no Austrian Empire. Spain became a republic and eventually a constitutional monarchy. During the 1963 conclave, Generalissimo Francisco Franco made an unsuccessful attempt to block the election of Cardinal Giovanni Montini. He sent the College of Cardinals some "advice" through Cardinal Arcadio Larraona, a native of Spain who was then the Prefect of the Congregation of Rites. It was carefully drafted to fall outside the forms of influence that Pius X had prohibited, but the cardinals nevertheless thought it outrageous.
