Asher Sisneros

The High Middle Ages were littered with imperial and papal conflicts. The Hohenstaufen family was notorious for garnering the hatred of various popes. From a glance, a student of history may get the impression that popes were continually engaged in proxy wars with the Holy Roman emperors. Such an impression would be accurate. Though the Hohenstaufens were not the only imperial dynasty to gain papal disapproval, they certainly received the spotlight because of their undiplomatic means of attaining their goals. However, one cannot help but wonder why the popes were continually at odds with the Holy Roman emperors. 

Before delving any further, it is important to briefly address what the Holy Roman Empire was. It was not Rome, as it may appear at first glance. Barbarian attacks put pressure on every side of Rome’s borders. By AD 410, the Visigoth leader Alaric burned Rome to the ground. It was the first time the city of Rome had suffered a tremendous defeat in over eight hundred years. Though they formerly held a firm military grip over the civilized world, Alaric’s invasion marked the beginning of the end for Rome. The Empire never recovered, and the Vandals sacked Rome a second time forty years later, with the Western Roman Empire officially collapsing in AD 476. Emperor Constantine built Constantinople on top of the former city, Byzantium, in AD 330. Over the years, the city gained political, religious, and economic power. In time, it even surpassed Rome in cultural influence. Constantinople was not affected by Rome’s collapse in AD 476. The various Byzantine emperors even envisioned retaking Rome from the barbarian hordes, but those ambitions were unsuccessful in the long term. Eventually, Frankish and Byzantine missionaries converted many of the barbarian nations. Those nations rallied behind the unified papal power. However, patriarchs in the East disputed papal authority, stating that all patriarchs were equivalent in authority and that no single man had a right to quasi-rule the entire Church. This dispute led to the Great Schism of AD 1054, when the West and East broke apart religiously, forming the Catholic and Eastern Orthodox distinction. Rallying behind papal authority, the West even engaged in various Crusades to retake Jerusalem from the Muslims. This unified religious state under papal authority became known as Christendom. In Christendom, Germany inherited imperial authority. The Frankish king Charlemagne was crowned as emperor by the Pope in AD 800, officially marking the beginning of the Holy Roman Empire. 

Pope Adrian crowned Fredrick Barbarossa as the Holy Roman emperor in AD 1152. The prince-electors favored Fredrick because he was a member of both the two most powerful Frankish dynasties. His father was a Hohenstaufen, while his mother was a Welf. The prince-electors viewed this political unification favorably, as the Emperor would not side with any particular family. However, Pope Adrian’s successor, Pope Alexander (r. 1159-1181) vehemently opposed Fredrick Barbarossa because of his expansionist foreign policy. As the old political adage goes, “Politicians want to stay politicians.” The same was true of Emperor Fredrick. The feudalist system gave his imperial crown instability. He was constantly threatened by powerful lords and neighboring kings. To combat the ramifications of feudalist decentralization and garner power behind the imperial crown, the Emperor invaded Lombardy for its vast wealth. However, the military expansion was a threat to papal independence. 

The Catholic Church had retained independence from the influence of monarchs. Following the Great Schism, the Byzantine Empire in Constantinople suffered the opposite fate. By embracing imperial authority and rejecting papal authority, the Eastern Orthodox suffered from an imperial hand that reached into every sphere of life, even governing their church. The division between the state’s and church’s authority was not respected in the East as it was in the West. Thus, the West was very cautious regarding imperial authority, seeing the negative consequences of the imperial intervention in religious affairs that occurred in the East. The Pope felt threatened by Fredrick’s invasion of Northern Italy and Lombardy because if his campaign was successful, Rome would be surrounded by one crown. That threatened papal independence. The Catholic Church reaped the numerous benefits of a feudalist system of government, but under a centralized rule, completely surrounded, the Pope worried that Fredrick might subdue the Church under the power of the crown. 

Thus, the Pope supported the Lombard League resisting Fredrick. Moreover, he also commanded the Emperor to cease his military expansion, going so far as to excommunicate him. The tremendous falling out between the Pope and the Emperor reached unprecedented levels. Frederick began supporting antipopes and robbing papal supporters. 

All of that said, it would be an injustice to say Fredrick was uninstigated. Though Fredrick certainly longed for the wealth in Northern Italy, that was not his sole motivation. It was more personal and in fact, a direct challenge to the Pope. The Pope had given William the 1st, king of Sicily, lands that formerly belonged to Fredrick. The Pope claimed that popes had the authority to divide lands and depose kings and emperors because they were all papal vassals. In other words, while he exercised dogmatism in distinguishing Church and State authority when monarchies exercised their authority in the Church, he somehow believed it was okay for popes to govern state authorities. Such was the dual standard. Frederick acknowledged this dual standard and partly attacked Northern Italy to defy the Pope. 

The imperial and papal conflicts during the High Middle Ages did not end with the death of Fredrick Barbarossa, however. The phenomenon continued. Just like Barbarossa, future emperors such as Emperor Otto and Emperor FredrickⅡ expanded militarily. 

Otto obtained papal support by promising to never invade Southern Italy. He was crowned in AD 1209. Immediately after gripping the crown, he invaded Southern Italy. In response, Pope Innocent retracted all support and pushed to crown Fredrick II. Though Otto might have been successful in claiming territories in Southern Italy, he expanded his borders too much, overestimating his military strength. His leveraged position crumbled after a failed expansion into France, making Fredrick II emperor. 

Frederick II obtained authority in Southern Italy and in Sicily due to his father’s marriage to Constance, the queen of Sicily. Pope Innocent III crowned him as Holy Roman emperor following Otto’s deposition. However, Frederick only earned papal support because he promised to break up Sicily and the Holy Roman Empire. The Pope did not want both those territories under one monarch’s rule. Frederick agreed to give up Sicily upon assuming the imperial throne. However, he ignored those promises and combined the Holy Roman Empire with Sicily, sparking the wrath of the Pope. Matters escalated when he made repeated promises to launch a Crusade to retake Jerusalem. The 5th Crusade was launched against al-Kamil, and the Crusaders fully expected Fredrick to provide them with reinforcements. However, those reinforcements never came. As a result, the Muslims reclaimed Damietta in AD 1221, and the Christians were expelled from the region. However, Frederick did accomplish a major feat when launching the 6th Crusade. He calmly stood before al-Kamil and made a peace proposal with the Muslims. The two came to an agreement stating that Christians could safely travel to Jerusalem on a pilgrimage if Jerusalem was not outfitted as a military base. Al-Kamil was not comfortable with having a Christian base within his borders. Thus, though Fredrick did stall in engaging in a Crusade, he did organize peace with the Muslims, something the prior Christian leaders failed to do. However, some historians argue that the 6th Crusade was illegitimate because Fredrick was previously excommunicated by the Pope for stalling during the 5th Crusade. Regardless, he successfully made peace with the Muslims, and that cannot be discounted. Despite that, the Pope excommunicated him again in AD 1239 for launching a military expansion into Italy. In response, Frederick expelled all friars in Sicily and began imprisoning bishops and robbing patriarchs/sees. The dissension came to blows when the Pope deposed Fredrick and when Fredrick called on Christian monarchs to attack the cardinals and the Pope. The long and bloody feud finally came to an end when Fredrick died in AD 1250.

To conclude, what caused the imperial and papal conflicts during the High Middle Ages? Part of it was military expansion, and in the case of Fredrick the 2nd, not speedily helping the 5th Crusade. Whenever an emperor expanded their borders around Rome, they—directly or indirectly—threatened papal independence. Under such threats, the popes enforced self-preservation tactics. Theologians can debate whether placing an entire region under interdict because of the sins of a monarch is ethical. However, that is an unnecessary rabbit hole when purely discussing what happened. The Hohenstaufen family was notorious for earning papal dissension. Their obsession with expanding into Italy weakened their position back home in Germany. In a way, their campaign to subdue Italy was futile and even counterproductive. Such expansionist foreign policies always end in disaster. When a kingdom expands to the point of being unmanageable, that kingdom will always crumble. American policymakers would be wise to take note. Those who do not study history are doomed to repeat it. However, military expansion was not the only reason for the imperial and papal conflicts during the High Middle Ages. Some may argue that—and it was certainly a factor—but the issue was much deeper. Ultimately, the feud arose because popes feared imperial intervention in the church, and emperors rejected papal authority in the state. In the end, the imperial and papal conflicts during the High Middle Ages were necessitated by blurry lines between jurisdictional authority.