The papacy was intimately allied with the Roman Empire, with the empire of Charlemagne, and with the German or Holy Roman Empire revived by Otto.  In this last the ecclesiastical element was of paramount importance, but the emperor was the supreme authority.  From that authority Gregory VII. resolved to free the pontificate, through the claim that no appointment by a layman to ecclesiastical office was valid; while the pope stood forth as universal bishop, a crowned high-priest.  To this supremacy the French first offered effectual resistance, issuing in the captivity of Avignon.  Germany followed suit, and the schism of the church was closed by the secular princes at Constance and Basle.  The papacy was restored in form, but not to its old supremacy.

The pontificates of Sixtus IV. and the egregious Alexander VI. were followed by the militant Julius II., who aimed, with some success, at making the pope a secular territorial potentate.  But the intellectual movement challenged the papal claim, the direct challenge emanating from Germany and Luther.  But this was at the moment when the empire was joined with Spain under Charles V. The Diet of Worms pointed to an accord between emperor and pope, when Leo X. died unexpectedly.  His successor, Adrian, a Netherlander and an admirable man, sought vainly to inaugurate reform of the Church from within, but in brief time made way for Clement VII.

Hitherto, the new pope’s interests had all been on the Spanish side, at least as against France; everything had been increasing the Spanish power in Italy, but Clement aimed at freedom from foreign domination.  The discovery of his designs brought about the Decree of Spires, which gave Protestantism a legal recognition in the empire, and also the capture and sack of Rome by Frundsberg’s soldiery.  Charles’s ascendancy in Italy and over the papacy was secured.  Clement, now almost at his beck, would have persuaded him to apply coercion to the German Protestants; but this did not suit the emperor, whose solution for existing difficulties was the summoning of a general council, which Clement was quite determined to evade.  Moreover, matters were made worse for the papacy when England broke away from the papal obedience over the affair of Katharine of Aragon.

Paul III., Clement’s immediate successor, began with an effort after regeneration by appointing several cardinals of the Contarini type, associates of the Oratory of Divine Love, many of whom stood, in part at least, on common ground with avowed Protestants, notably on the dogma of justification by faith.  He appears seriously to have desired a reconciliation with the Protestants; and matters looked promising when a conference was held at Ratisbon, where Contarini himself represented the pope.

Terms of union were even agreed on, but, being referred to Luther on one side and Paul on the other, were rejected by both, after which there was no hope of the cleavage being bridged.  The regeneration of the Church would have to be from within.