The bishops of Rome did not extend their power over the Western parts all at once; but it was introduced from time to time, by degrees, by various artifices, and under various pretences. What chiefly contributed to its growth was, first, the emperors choosing other places of residence besides Rome; for, by their constant presence there, they might easily have kept under the ambitious designs of the bishops. In the next place, the Western empire was divided into several new kingdoms, erected by the several barbarous and pagan nations, and these, having been converted to the Christian faith by the direction of the Romish Church, thought themselves obliged to pay her the profoundest respect.

In the fifth century, the bishops on this side of the Alps began to go to Rome, to visit the sepulchres of St. Peter and St. Paul. This voluntary devotion insensibly grew into a necessity. From hence it was easy for the popes afterwards to pretend, that the bishops ought to receive their confirmation from Rome. Besides, some other bishops and churches, that were novices in comparison of the ancient Roman Church, used to refer themselves to, and ask the advice of, the Church of Rome, concerning matters of great consequence, and the true interpretation of the canons. Hence the bishops of Rome, perceiving their answers were received as decisions, began to send their decrees before they were demanded. And hence they set themselves up as judges of the differences arising between the bishops, and, encroaching on the right and jurisdiction of the metropolitans, proceeded to suspend and depose whom they thought fit. At the same time, by making void the decisions of the provincial synods, they so diminished their authority, that by degrees they were quite abolished. Add to this, that Gregory VII. forced the bishops to take an oath of fealty to the popes, and by a decree enacted that none should dare to condemn any one, who had appealed to the pope. Nor did they forget to send legates or nuncios to all places, whose business was to exercise, in the pope’s name, the same authority, which had formerly belonged to the bishops and provincial synods. (See Legate.)

It is certain that many Romish bishops, especially among those on this side the Alps, were to a late period opposed to the pope’s authority; which evidently appeared at the Council of Trent, where the French and Spanish bishops insisted very strongly to have it decided, that bishops are obliged to residence by the law of God; the consequence of which was, the deriving their authority from God alone. The pope met with great difficulty before he could surmount this obstacle; and therefore it is very likely this will be the last council, since the pope will scarce put his grandeur to the hazard and decision of such another assembly. Not to mention that they are now of no farther use, since the Jesuits and others have taught, that the pope is infallible, and superior to councils. However that may be, the bishops are obliged for their own sakes not to withdraw themselves from the pope’s jurisdiction, since thereby they would fall under the civil power, and would be obliged to seek protection from their sovereigns, who must be potent princes, if they could protect them against the pope; so that they think it wiser, of two evils to choose the least.

The spiritual monarchy of Rome could not have been established, had its bishops continued dependent on any temporal prince; and therefore the popes took their opportunity to exempt themselves from the jurisdiction of the Greek emperors, whose authority was mightily decayed in Italy. This was greatly forwarded by the dispute concerning the use of images. For the emperor Leo Isaurus having quite ejected them out of the churches, Pope Gregory II., who stood up for the images, took occasion to oppose him, and stirred up the Romans and Italians to refuse to pay him tribute; by which means the power of the Greek emperors was lost in Italy, and these countries began to be free and independent of any foreign jurisdiction.

The pope, having freed himself from the authority of the emperors of Constantinople, and being in danger from the Lombards, who endeavoured to make themselves masters of Italy, had recourse for protection to the kings of France. Pepin, and afterwards Charles the Great, having entirely subdued the Lombards, these princes gave to the papal chair all that tract of land, which had been formerly subject to the Greek emperors. To obtain this gift, it is said, the pope made use of a fictitious donation of Constantine the Great, which, in those barbarous times, was easily imposed upon the ignorant world. By virtue of this grant, the popes pretended to a sovereign jurisdiction over these countries; which the people at first refused to submit to, thinking it very strange, that the pope, who was an ecclesiastical person, should at the same time pretend to be a temporal prince. When, therefore, the Romans mutinied against Leo III., he was forced to seek for assistance from Charles the Great, who restored the pope. On the other hand, the pope and people of Rome proclaimed Charles emperor; whereby he was put in possession of the sovereignty of that part of Italy, which formerly belonged to the governors of Ravenna, and the other remnants of the Western empire; so that the popes afterwards enjoyed these countries under the sovereign jurisdiction of the emperor, who therefore used to be called the patron and defender of the Church, till the reign of the emperor, Henry VI.

The popes at length began to grow weary of the imperial protection, because the emperor’s consent was required in the election of a pope, and, if they were mutinous, the emperors used to check them, and sometimes turn them out of the chair. The popes, therefore, for a long time, employed various artifices to exempt themselves from the power of the emperors. To this end, they frequently raised intestine commotions against them. But the reign of Henry IV. furnished them with an opportunity of putting their designs in execution. For Pope Gregory VII., surnamed Hildebrand, had the boldness to excommunicate this emperor, on pretence that he made a traffic of church benefices, by selling them to all sorts of persons, whom he installed before they had taken orders. And, not satisfied with this, he cited the emperor before him, to answer to the complaints of his subjects, and declared him to have forfeited all right and title to the empire. This obliged the emperor to renounce the right of constituting bishops. And though his son, Henry V., endeavoured to recover what was forcibly taken away from his father, and made Pope Paschal a prisoner, yet were the whole clergy in Europe so dissatisfied, that he was obliged at last to resign the same right again into the pope’s hands. This affair gave rise to the factions of the Guelfs and Ghibelines, the first of which were for the pope, the latter for the emperor. The succeeding emperors found so much work in Germany, that they were not in a condition to look after Italy; whereby the pope had sufficient leisure to make himself sovereign, not only over his own possessions, but over all possessions pertaining to the Church.

But the pope, not satisfied with this degree of grandeur, quickly set on foot a pretension of far greater consequence. For now he pretended to an authority over princes themselves, to command a truce between such as were at war together, to take cognizance of their differences, to put their kingdoms under an interdict, and, if they refused submission to the see of Rome, to absolve their subjects from their allegiance, and to deprive them of their crowns. This has been attempted against many crowned heads, and put in execution against some of them. And for this abominable pretension they pleaded their fictitious decretals, (see Decretals,) which grant to the popes an unlimited power over all Christians whatever. Pope Boniface VIII. gave the world clearly to understand his meaning, at the jubilee kept in the year 1300, when he appeared sometimes in the habit of an emperor, and sometimes in that of a pope, and had two swords carried before him, as the ensigns of the ecclesiastical and civil power.

But the popes could not long enjoy this intolerable usurpation in quiet; for it was often called in question, till they were obliged to desist in part from their pretensions. In particular, Philip the Handsome, king of France, gave several great blows to the papal authority. But the ensuing schisms, and the double elections, when the opposite factions chose two different popes at the same time, contributed most towards weakening the power of the holy see. Hence an occasion was taken to bridle the pope’s authority by general councils, which often proceeded so far as to depose the holy fathers. Therefore it is not to be wondered that, since the Council of Trent, the popes have been very averse to the calling of general councils, and seem to have bid adieu to them for ever. To this may be added, that the translation of the papal chair, by Clement V., from Rome to Avignon, where the popes constantly resided for seventy years together, carried along with it several inconveniences, which proved greatly prejudicial to the ecclesiastical monarchy. Among others, the pope’s authority being founded upon this belief, that St. Peter had been at Rome, and by his presence had communicated a particular prerogative and holiness to that chair, it was very much questioned whether the same could be transferred to Avignon.

But, when the ecclesiastical monarchy seemed to be come to the pinnacle of its grandeur, when all the Western parts were either in communion with, or in obedience to, the Church of Rome, by the influence of the Reformation, the pope became only the spiritual head of a sect, and eventually, as a civil power, of very slight importance.

The manner of the election of a pope is as follows: nine or ten days after the funeral of a deceased pope, the cardinals enter the conclave, which is generally held in the Vatican, in a long gallery, where cells of board are erected, covered with purple cloth, one for each cardinal. (See Conclave.)