Mayor of the Palace of the whole Frankish kingdom (both Austrasia and Neustria), and later King of the Franks; born 714; died at St. Denis, 24 September, 768. He was the son of Charles Martel. Pepin and his older brother Carloman were taught by the monks of St. Denis, and the impressions received during their monastic education had a controlling influence upon the relations of both princes to the Church. When the father died in 741 the two brothers began to reign jointly but not without strong opposition, for Griffon, the son of Charles Martel and the Bavarian Sonnichilde, demanded a share in the government. Moreover, the Duke of the Aquitanians and the Duke of the Alamannians thought this a favourable opportunity to throw off the Frankish supremacy. The young kings were repeatedly involved in war, but all their opponents, including the Bavarians and Saxons, were defeated and the unity of the kingdom re-established. As early as 741 Carloman had entered upon his epoch-making relations with St. Boniface, to whom was now opened a new field of labour, the reformation of the Frankish Church. On 21 April, 742, Boniface was present at a Frankish synod presided over by Carloman at which important reforms were decreed. As in the Frankish realm the unity of the kingdom was essentially connected with the person of the king, Carloman to secure this unity raised the Merovingian Childeric to the throne (743). In 747 he resolved to enter a monastery. The danger, which up to this time had threatened the unity of the kingdom from the division of power between the two brothers, was removed, and at the same time the way was prepared for the deposing of the last Merovingian and for the crowning of Pepin. The latter put down the renewed revolt led by his step-brother Griffon, and succeeded in completely restoring the boundaries of the kingdom. Pepin now addressed to the Pope the suggestive question: In regard to the kings o the Franks who no longer possess the royal power, is this state of things proper? Hard pressed by the Lombards, Pope Zacharias welcomed this advance of the Franks which aimed at ending an intolerable condition of things, and at laying the constitutional foundations for the exercise of the royal power. The pope replied that such a state of things was not proper. After this decision the place Pepin desired to occupy was declared vacant. The crown was given him not by the pope but by the Franks. According to the ancient custom Pepin was then elected king and soon after this was anointed by Boniface. This consecration of the new kingdom by the head of the Church was intended to remove any doubt as to its legitimacy. On the contrary, the consciousness of having saved the Christian world from the Saracens produced, among the Franks, the feeling that their kingdom owed its authority directly to God. Still this external cooperation of the pope in the transfer of the kingdom to the Carolingians would necessarily enhance the importance of the Church. The relations between the two controlling powers of Christendom now rapidly developed. It was soon evident to what extent the alliance between Church and State was to check the decline of ecclesiastical and civil life; it made possible the conversion of the still heathen German tribes, and when that was accomplished provided an opportunity for both Church and State to recruit strength and to grow.
Ecclesiastical, political, and economic developments had made the popes lords of the ducatus Romanus. They laid before Pepin their claims to the central provinces of Italy, which had belonged to them before Liutprand's conquest. When Stephen II had a conference with King Pepin at Ponthion in January, 754, the pope implored his assistance against his oppressor the Lombard King Aistulf, and begged for the same protection for the prerogatives of St. Peter which the Byzantine exarchs had extended to them, to which the king agreed, and in the charter establishing the States of the Church, soon after given at Quiercy, he promised to restore these prerogatives. The Frankish king received the title of the former representative of the Byzantine Empire in Italy, i.e. "Patricius", and was also assigned the duty of protecting the privileges of the Holy See.
When Stephen II performed the ceremony of anointing Pepin and his son at St. Denis, it was St. Peter who was regarded as the mystical giver of the secular power, but the emphasis thus laid upon the religious character of political law left vague the legal relations between pope and king. After the acknowledgment of his territorial claims the pope was in reality a ruling sovereign, but he had placed himself under the protection of the Frankish ruler and had sworn that he and his people would be true to the king. Thus his sovereignty was limited from the very start as regards what was external to his domain. The connection between Rome and the Frankish kingdom involved Pepin during the years 754-56 in war with the Lombard King Aistulf, who was forced to return to the Church the territory he had illegally held. Pepin's commanding position in the world of his time was permanently secured when he took Septimania from the Arabs. Another particularly important act was his renewed overthrow of the rebellion in Aquitaine which was once more made a part of the kingdom. He was not so fortunate in his campaigns against the Saxons and Bavarians. He could do no more than repeatedly attempt to protect the boundaries of the kingdom against the incessantly restless Saxons. Bavaria remained an entirely independent State and advanced in civilization under Duke Tassilo. Pepin's activity in war was accompanied by a widely extended activity in the internal affairs of the Frankish kingdom, his main object being the reform of legislation and internal affairs, especially of ecclesiastical conditions. He continued the ecclesiastical reforms commenced by St. Boniface. In doing this Pepin demanded an unlimited authority over the Church. He himself wished to be the leader of the reforms. However, although St. Boniface changed nothing by his reformatory labours in the ecclesiastico-political relations that had developed in the Frankish kingdom upon the basis of the Germanic conception of the State, nevertheless he had placed the purified and united Frankish Church more definitely under the control of the papal see than had hitherto been the case. From the time of St. Boniface the Church was more generally acknowledged by the Franks to be the mystical power appointed by God. When he deposed the last of the Merovingians Pepin was also obliged to acknowledge the increased authority of the Church by calling upon it for moral support. Consequently the ecclesiastical supremacy of the Frankish king over the Church of his country remained externally undiminished. Nevertheless by his life-work Pepin had powerfully aided the authority of the Church and with it the conception of ecclesiastical unity. He was buried at St. Denis where he died. He preserved the empire created by Clovis from the destruction that menaced it; he was able to overcome the great danger arising from social conditions that threatened the Frankish kingdom, by opposing to the unruly lay nobility the ecclesiastical aristocracy that had been strengthened by the general reform. When he died the means had been created by which his greater son could solve the problems of the empire. Pepin's policy marked out the tasks to which Charlemagne devoted himself: quieting the Saxons, the subjection of the duchies and lastly, the regulation of the ecclesiastical question and with it that of Italy.