The ultimate aspiration of Gregory VII (1073–1085), as outlined in his Dictatus Papae (1075), was fully realized with Innocent III, the most powerful pope of the entire Middle Ages.
Under Innocent III, the papacy solidified its primacy throughout the Western Church and its authority—moral and beyond—over all European states. He embodied the Augustinian concept of the Civitas Dei, bolstered by the Donation of Constantine, which was then regarded as genuine.
At this time, the Church appeared as the true Imperium Romanum, with the papacy claiming absolute power over the world. The pope became the Caput Christianitatis, presiding over many peoples united in a single faith.
Innocent III was a deeply religious man, rich in inner spirituality, dedicated to asceticism, and steadfast in his role as pastor and priest. Born Lotario, from the noble Segni family, in 1160, he studied theology and canon law in Paris and Bologna before being inducted into the College of Cardinals by his uncle, Pope Clement III.
Despite his small stature and fragile health, he was a man of extensive learning, remarkable moral strength, and keen intellect. He possessed a broad perspective and addressed all matters with prudence. His involvement in temporal affairs was solely to safeguard the Church’s autonomy and prevent it from becoming an imperial fiefdom.
Innocent III did not claim the right to elect the emperor but reserved the authority to evaluate the moral qualities of the candidate.
To Innocent III, the affairs of this world were subordinate to God’s divine order. Thus, sovereigns and princes were obliged to bow to God’s will. He envisioned the world as a great hierarchy with Christendom at its apex, where the pope served as an intermediary between God and humanity, judging all but answerable only to God.
He recognized the importance of mendicant orders within the Church, particularly approving the Order of St. Francis, understanding that these orders would drive the Church’s renewal, which had become overly entangled in worldly affairs. Innocent shared their detachment from wealth and grandeur, abstaining from such distractions himself.
Innocent III’s legacy can be understood through four key areas. First, in political leadership, Innocent III brought stability to Rome and the Papal States, effectively defending them against expansionist threats and imperial claims. His governance reinforced papal authority and ensured the Church’s influence in temporal matters. Second, in the realm of crusades and unity, he played a pivotal role in organizing the Fourth Crusade, aiming to reclaim the Holy Land. Additionally, he sought to reconcile the Western and Eastern Churches, emphasizing the need for unity in Christendom. Third, Innocent III focused on combatting heresies, actively opposing movements like the Cathars and Waldensians. His efforts to preserve orthodox faith and practice defined much of his papacy’s confrontational stance against perceived threats to Church doctrine. Finally, his commitment to church reform culminated in the Fourth Lateran Council, a historic assembly of 500 bishops and 800 abbots. This council synthesized his reform efforts, addressing themes such as Church administration, the moralization of the clergy, the promotion of the Fourth Crusade, and the suppression of heresies, solidifying Innocent III’s influence and marking the zenith of his papal reign.
Innocent III and the Struggle with the Hohenstaufens
Innocent III’s pontificate and the 13th century as a whole were marked by the papacy’s struggle against the Hohenstaufen dynasty, which resisted its claims, threatening the libertas ecclesiae. The empire sought to restore the dominance it had enjoyed under the Ottonians.
After complex events, Innocent III deposed Emperor Otto IV, who had reneged on his pro-papal promises, and supported Frederick II’s ascension as King of Germany in 1212. However, Frederick II soon sought to subordinate the Church to his authority, envisioning a unified religious and political power vested in the emperor.
Pope Gregory IX (1227–1241) sought to resolve the conflict through a council, which Frederick II forcibly prevented. Innocent IV (1243–1254) convened a council in Lyon that excommunicated and deposed Frederick II. With the assistance of Charles of Anjou, the Hohenstaufen dynasty was ultimately defeated, culminating in the execution of Conradin of Swabia in Naples. However, Charles of Anjou himself proved problematic for the papacy.
The Crisis of the System
The protracted struggle with the Hohenstaufens divided Italy into Guelfs (papal supporters) and Ghibellines (imperial supporters), fracturing political forces and creating internal divisions.
Within the College of Cardinals, a growing French dominance began with Urban V (1362–1370), laying the groundwork for the Avignon Papacy. Personal ambitions among noble families, such as the Colonna and Orsini, further compounded these divisions, complicating papal elections and leading to long periods of vacancy.
This dynamic gave rise to an unseemly strategy: electing either a decrepit candidate for a short pontificate or one lacking influence, thereby preserving the status quo. In this context, the hermit monk Pietro da Morrone was elected as Celestine V (1241), amidst enthusiasm from Franciscans and spiritualists hoping for a return to the primitive Church. However, he abdicated within months under the pressure of Benedetto Caetani, who succeeded him as Boniface VIII (1294–1303).
Boniface VIII, a figure of great cultural, moral, and political stature, reorganized the Church and sought to mediate conflicts, including those between France and England. However, his clash with Philip IV of France ultimately led to his humiliation at Anagni and marked the end of the high medieval papacy’s glory.
The Papacy’s Claim to Hierarchical Leadership
Following Gregory VII, the Concordat of Worms, and Innocent III, the Church achieved internal autonomy, free from imperial domination. This autonomy extended to temporal matters, including the Papal States, feudal territories, the imperial crown, and the ability to command any authority.
The medieval papal imperium was justified by a shift from imperial theocracy—where the Church was seen as an extension of imperial power—to papal hierocracy. This shift reflected not domination but a new worldview where creation served the redemption accomplished by Christ, represented in the Church, whose pinnacle was the pope.
The Theory of the Two Swords
The relationship between spiritual and temporal power was illustrated using metaphors such as body-soul, sun-moon, and spiritual-temporal swords. The “two swords” analogy, based on Luke 22:38, was particularly favored due to its scriptural basis.
The gladius spiritualis had two levels: spiritual sanctification and visible, coercive authority expressed through legal and punitive powers. When applying ecclesiastical law to the defiant, the gladius temporalis provided material coercion to enforce decisions.
This duality clarified the interaction of spiritual and temporal powers, highlighting the Church’s supervisory role over worldly authority and its mechanisms for maintaining order and addressing sin. Understanding this dynamic is key to grasping the functioning of the Inquisition.