This Empire had been a civilizing power. It had supported the Papacy, as an oak supports the creeper that clings to it; and in its decline and fall it pulled the Papacy down with it. Without such support the Papacy could maintain neither dignity abroad nor order at home. This lesson the Church learned once through the outrages inflicted upon Pope Leo, but forgot it; and required the experience of a hundred and fifty years to learn it a second time. In theory Papacy and Empire were co-equal powers, religious and secular, together carrying on the noble task of God's government on earth. In practice, as their respective rights and powers had not been definitely set off, they could not agree; each wished to be master. The relations between the two constitute the great axis on which mediæval politics revolve, and for a long time must serve as the main motive of our story. The contest between them for mastery resembles a fencing match, in which the Pope thrusts at the Emperor's crown, the Emperor parries, and lunges back at the papal tiara. For convenience we divide the match into two bouts, and first take the Pope's attack.
At the famous coronation on Christmas day, 800, Charlemagne and Leo stood side by side, co-labourers in the great task of reconstructing Europe. But once the coronation over, the two undefined authorities jostled each other. Charlemagne, to whom government was as much a religious as a secular matter, though he had accepted his Imperial crown at the hands of the Pope, did not regard papal participation necessary for the continuance of the Imperial dignity. At Aachen, 813, he crowned his son Louis the Pious co-Emperor, without the help of Pope or priest. This thrust must have carried discomfiture to the banks of the Tiber. But with Charlemagne's weak successors the astute Papacy scored hit after hit. Louis the Pious submitted to be recrowned by the Pope, so did his son, Lothair, and his grandson Louis II; and their two successors were also crowned by the Pope. This sequence of palpable hits won this bout and secured for the Papacy beyond dispute the prerogative of crowning the Emperors.
If we now turn to that part of the game where Emperor lunged and Pope parried, we find a more complicated situation. A third player takes a hand, to the confusion of the game and to the great detriment of the papal defence. This third player is the Roman people, who believed that the Senatus Populusque Romanus still possessed their ancient prerogatives, and had the right to appoint both Emperor and Pope. Their claim to elect the Emperor was flimsy enough, being merely the memory of an empty form, and is not of enough consequence to stop for; but their claim to interfere in the papal election was of the highest importance. It arose from the anomalous nature of the Papacy. The Pope was bishop of Rome, and as such his election lay in the hands of the clergy and people of Rome; he was also the ruler of central Italy, and as such the barons there were interested in his election; and, in addition, he was head of all the Christian Churches in the West, and so all western Christendom, and the Emperor as its temporal lord, was likewise concerned. The fact was that no definite method of papal election and confirmation had been settled upon during these disturbed centuries. The original practice had been for the Roman churches, priests, and laymen together assembled, to make the election; subsequently the senate, or the army, or the nobles, had represented the lay body of electors; but whoever represented the laymen, they and the clergy made the election; which was then submitted to the Emperor, or his representative, for scrutiny and confirmation. The submission of the Roman election to the examination of a Byzantine Emperor had never been acceptable in Rome, and after the breach over iconoclasm, the practice ceased. Naturally, on the revival of the Roman Empire in the West, the new Emperors claimed the old Imperial right of supervision; naturally, also, the papal party resisted the fresh exercise of the old prerogative. Here was a situation for a scrimmage, but any clear account of the papal elections in Rome, supposing such were possible, would be too minute; this narrative must confine itself to the main passes between the papal party and the Emperors.
After the death of Charlemagne (no papal election occurred during his lifetime) several Popes were elected and consecrated without previously consulting the Emperor. On the other hand, in the next reign the Imperial deputy made the Romans take oath that no Pope should be consecrated without the approval of the Emperor. What was done at the following election is not known, but at the second the Pope was not consecrated until the Emperor had ratified the proceedings. Thereafter the Imperial right was acknowledged in theory, though in practice the elected Pontiffs did not always wait for Imperial confirmation.
With the fall of the Carlovingian Empire the fencing match ceased for lack of an Imperial contestant. The score stood thus: each had succeeded in the attack, the Papacy had won its right to bestow the Imperial crown, and the Empire had won, though not so definitely, its right to supervise the election of a Pope. We must now pass to this Imperial interregnum knowing that when the Empire shall be revived, the match will begin anew and the combatants, with foils unbated and envenomed, will fight to a finish.
The Imperial interregnum, nominally interrupted by one German and several Italian make-believe Emperors, lasted for three generations; no Imperial power was exercised from 875 to 962. It is a murky period in which shadows wander about; but before taking our candle and descending into the gloom, we will turn to the one bright spot, the career of a great Pope, Nicholas I (858-867).
This Pope, in spite of the decadence of the Papacy, won immense prestige for it by two successful assertions of cosmopolitan authority. The King of Lorraine, brother to Louis II, the Emperor, wished to put away his wife and marry another woman. The innocent queen, with the sanction of the clergy of the kingdom, was divorced and forced to enter a convent; and, with the consent of his clergy, the king married the other woman. The wronged queen appealed to the Pope, who sent his legates to investigate the affair; but the king bribed the legates and succeeded in getting a decision from the local synod in his favour, although, in fact, the whole matter had been a shocking scandal. Thereupon the king sent the archbishops of Cologne and of Trier, the two great ecclesiastical dignitaries of the kingdom, to announce this verdict of acquittal. The Pope, "professing," as his enemies said, "to be imperator of the whole world," seized his opportunity; he espoused the cause of the innocent queen, annulled the fraudulent proceedings, and excommunicated and deposed the two archbishops. The king applied to the Emperor for help, and the Emperor went to Rome, but could obtain no concession. The Pope stood like a rock. He allied himself with France and Germany, and threatened to excommunicate the sinning husband and all his bishops. The king was obliged to submit. The usurping wife was excommunicated and banished, and the papal legate conducted the divorced queen back to the royal palace. Thus the Papacy not only established a great precedent for the supremacy of the spiritual over the temporal power, but also stood conspicuous before the world as the champion of the weak and oppressed and the defender of morality and justice.
It would be difficult to overrate the effect of this papal achievement. It may be that the Papacy stood forth as champion of innocence when policy coincided with righteousness; but it was the righteousness and not the policy which gave the Papacy strength. One can imagine, in days when brutal barons, scattered in strongholds all over the country, were the normal forms of power and authority, what effect such news had upon the people. A pilgrim from across the Alps, a peddler, or some poor vagrant, enters a village huddled at the foot of a hill, on which stands a great castle where a drunken lord revels with his mistresses, and recounts to the assembled peasants, serfs, and slaves, how the Holy Father, in the name of God, had commanded a greater lord, in a greater castle, to put away his mistress and bring back his wife, and how that lord had got down on his knees and had done the Holy Father's bidding.
The second case was the victory of papal authority over the spirit of nationality in the Church. When the incipient nations of France and Germany, having separated from the Empire, had begun to be self-conscious, the spirit of nationality naturally showed itself in ecclesiastical matters as well as in political matters. There was obvious likelihood that the nations would govern themselves ecclesiastically as well as politically. Should they do so, the papal supremacy would fall just as the Imperial supremacy had fallen, and the unity of the Church would be shattered just as the Empire had been. Here was certainly a great danger to the Papacy, and probably a great danger to Christianity and civilization; at least so Nicholas thought. He resolved to meet it boldly. His opportunity came when a French (West Frankish) bishop appealed to Rome against the action of his metropolitan. The metropolitan objected that there was no precedent for papal action in such a case; he did not deny that the Pope had certain appellate functions, but said that if the Pope interfered directly in the discipline of bishops, the power of the metropolitan would be impaired. It is needless to say that this argument did not produce the result that the metropolitan desired. There was nothing the Papacy wanted more than that its central government should act directly everywhere, and that all bishops should be dependent upon Rome; that was the very principle of papal supremacy. The issue would determine whether the Papacy was to be an autocratic power, or a limited court of appeal. Nicholas was able to take advantage of the troubled political situation to enforce direct papal authority, and so added an immense prerogative to the papal power.
Apart from this imperial ecclesiastical principle the latter episode is especially interesting on account of the character of the evidence produced by the Pope to maintain his position. This evidence consisted of a new compilation of Church law which appeared somewhat mysteriously about this time. Theretofore Church law had consisted of a collection of precepts taken from the Bible, from the early Fathers, from decrees of Councils, and also of letters, called decretals, written by the bishops of Rome, but none of these decretals was earlier than the time of Constantine. The fact, that there were no papal decretals prior to Constantine, seemed to imply, at least to the sceptically minded, that papal authority had really begun at the time of Constantine and not at the time of St. Peter. To the ardent papist such an idea was incredible. Nicholas now produced a new batch of documents. Among these was the Donation of Constantine, of which I have spoken. Others were papal decretals, which purported to come from Popes of the third and second centuries, and to prove that papal jurisdiction over other bishoprics had been exercised almost as far back as the time of St. Peter. These new appearing documents placed the Pope not only above kings, but above metropolitans and provincial synods, and justified Nicholas in acting directly in the case of the West Frankish bishop, in the King of Lorraine's matrimonial affairs, and also in assuming to act as "imperator of the whole world." These documents, known as the Isidorian Decretals, were probably composed by some priest in France, not long before their use by Nicholas. For six hundred years they were believed to be genuine, and during that time rendered the Papacy great service by ranging the sentiment of law throughout Europe (at least until the revival of Roman law) on the side of the Papacy in its struggle with the Empire.