The Inheritance of Conflict: Partitioning an Empire

The story of Europe’s transformation from a unified Frankish empire into competing medieval kingdoms begins not with a single event, but with a recurring Carolingian dilemma: how to manage inheritance among multiple heirs. Following the death of Charlemagne in 814, his son Louis the Pious struggled to maintain the empire’s unity against the centrifugal forces of regionalism and aristocratic ambition. The subsequent generations would witness this struggle intensify, culminating in the permanent dissolution of Charlemagne’s achievement.

Lothair I initially managed to maintain some cohesion as co-emperor, but the partitions of the Frankish realm following fraternal conflicts created irreversible fractures. The idea of regular meetings among Carolingian brothers to uphold shared responsibilities—a noble attempt at preserving unity—proved fleeting against the reality of competing interests and territorial ambitions. By the time of Lothair’s death in 855, what had once been a unified empire under Charlemagne had fractured into five distinct realms: Middle Francia , East Francia, and West Francia.

This fragmentation represented more than just political division—it signaled the emergence of distinct regional identities that would eventually evolve into the nation-states of modern Europe. The Carolingian world was transforming from an empire held together by personal loyalty to a monarch into territories defined by geography, language, and local aristocracy.

The Treaty That Redrew the Map: Verdun 843

The Treaty of Verdun in 843 stands as one of history’s most consequential diplomatic agreements, establishing divisions that would echo through European history for centuries. The three surviving sons of Louis the Pious—Lothair I, Louis the German, and Charles the Bald—formalized the partition of the Carolingian Empire into three roughly equal portions based on revenue and resources rather than coherent geographical or ethnic boundaries.

Lothair received the Middle Kingdom, a long strip of territory running from the North Sea to central Italy, including the imperial title and the symbolic capitals of Aachen and Rome. Louis the German acquired East Francia, the Germanic-speaking territories east of the Rhine. Charles the Bald obtained West Francia, comprising most of modern-day France. This division created the rough outlines of what would become France, Germany, and the contested territories between them—particularly Alsace-Lorraine, which would remain a point of conflict into the twentieth century.

The treaty reflected the Carolingian practice of partible inheritance rather than primogeniture, a tradition that repeatedly weakened central authority. While intended to prevent conflict by providing for all heirs, this approach ultimately guaranteed competition and warfare among the various branches of the Carolingian dynasty.

The Imperial Title: Symbol of Unity or Catalyst for Conflict?

The imperial title, revived by Charlemagne in 800, became both a symbol of unity and a source of contention among his descendants. While theoretically granting precedence over other rulers, the title carried diminishing practical authority as the empire fragmented. The possessor of the imperial crown claimed leadership of Christendom but increasingly struggled to exercise real power beyond their own territories.

This tension between symbolic authority and practical power became particularly evident in Italy, where imperial rule maintained its strongest connection to the concept of a unified Christian empire. The Italian peninsula, with its wealth, strategic importance, and proximity to the papacy, became the prize over which Carolingian rulers would repeatedly clash. Control of Italy meant not just territory and resources but also access to papal coronation, which could legitimize claims to superiority over other rulers.

Louis II . His reign demonstrated how imperial authority had become increasingly dependent on local Italian power structures and papal support rather than Frankish military might.

The Succession Crisis of 875: A Turning Point

The death of Louis II in 875 without male heirs created a critical juncture in Carolingian history—what historians would later recognize as the point at which reunification of the empire became impossible. Both surviving uncles, Charles the Bald of West Francia and Louis the German of East Francia, coveted not just Louis’s Italian territories but the imperial title that came with them.

Charles moved with decisive speed, having secretly secured promises of coronation from Popes Adrian II . When Louis II died on August 12, 875, Pope John VIII invited Charles to Rome for coronation, giving the West Frankish king a critical advantage over his East Frankish rival. This moment of opportunity created what would become the only imperial reign from West Francia—a historical anomaly that would later fuel French ambitions for centuries.

Charles’s swift crossing of the Alps and coronation in St. Peter’s Basilica on Christmas Day 875—exactly 75 years after his grandfather Charlemagne’s coronation—represented a brilliant political maneuver. Meanwhile, his brother Louis the German could only stage a symbolic protest by celebrating Christmas at Charles’s palace at Attigny, unable to prevent the coronation.

The Papacy as Kingmaker: Shifting Ecclesiastical Power

The succession crisis of 875 revealed the growing political role of the papacy in imperial affairs. Previously, papal involvement in imperial coronations had been largely ceremonial, acknowledging the military and political reality established by the Franks. Pope John VIII’s active choice between two equally legitimate candidates represented a significant expansion of papal authority in secular matters.

The Liber Pontificalis carefully documented how Louis II had twice held the bridle of Pope Nicholas I’s horse in 858, echoing Pepin’s similar act in 754. This symbolic act of submission traditionally demonstrated the emperor’s role as protector of the Church. By the time of Charles’s coronation, however, the papacy was asserting a more active role in selecting and legitimizing rulers.

This development reflected both the weakening of Carolingian authority and the papacy’s growing confidence in intervening in secular politics. The ceremony in St. Peter’s represented not just religious sanction but active political choice—a precedent that would influence papal-imperial relations for centuries.

Disappointed Expectations: The Limits of Imperial Power

Charles’s imperial reign quickly revealed the gap between the theoretical authority of the imperial title and its practical limitations. Pope John VIII had expected the new emperor to march south and confront the Saracen threat to Italian territories, but Charles focused instead on consolidating his position in northern and central Italy.

This divergence between papal expectations and imperial priorities highlighted a fundamental truth about the later Carolingian empire: the imperial title offered prestige and theoretical precedence but required military resources that often exceeded the holder’s means. The dream of universal empire was colliding with the reality of limited power and competing priorities.

The emperor’s appointment of his brother-in-law Boso of Vienne as his representative in Italy—married to Irmingard, daughter of Louis II—represented an attempt to govern through local intermediaries rather than direct control. This approach acknowledged the practical limits of Carolingian authority in the Italian peninsula.

Regional Resentment and Competing Narratives

The imperial coronation of Charles provoked strong reactions from his rivals, particularly in East Francia. The Annales Fuldenses , reflecting the East Frankish perspective, offered a scathing assessment of Charles’s actions: “He broke his promises and hastened to Rome with all speed. Like Jugurtha, he bought the support of the entire Roman senate with money, won its favor, and thus even Pope John yielded to his entreaties, placed the crown on his head, and called him emperor and Augustus.”

This account, while undoubtedly partisan, reveals several important dynamics. First, it shows the persistence of a unified Frankish identity that viewed such maneuvering as illegitimate. Second, it demonstrates how regional chronicles were developing distinct perspectives and narratives—an early form of national history. Finally, the reference to Jugurtha suggests the growing perception that imperial authority could be purchased rather than earned through merit or legitimacy.

The Legacy of Fragmentation: Emerging Kingdoms and Identities

The events of 875 and their aftermath accelerated the development of separate political entities in East and West Francia. Initially identified by the name of their rulers, these territories gradually developed institutional structures and aristocratic networks that would evolve into the kingdoms of France and Germany.

The existing boundaries, originally drawn for administrative convenience, began to define spheres of political activity that replaced the broader framework of the Frankish empire. Important noble alliances found new spaces for identity within these emerging kingdoms, laying the foundation for the regional principalities that would characterize high medieval politics.

This process of political fragmentation was neither clean nor immediate. The imperial title would change hands multiple times in the following decades, with East Francia briefly gaining supremacy in 881 and 896. Not until 924/925 would the question of imperial succession and the disposition of Lothair’s territories be temporarily settled, demonstrating the diversity of political actions and alliances among the Franks.

The Long Shadow: Carolingian Legacy in Medieval Europe

The dissolution of the Carolingian Empire created the political landscape that would define medieval Europe. The emergence of separate kingdoms in East and West Francia established the basic framework that would eventually develop into the Holy Roman Empire and the Kingdom of France.

The imperial title, though diminished, would be revived by Otto I in 962, beginning the tradition of German rulers seeking coronation in Rome. This practice would create centuries of tension between papacy and empire, between German rulers and Italian cities, between universal claims and particular realities.

West Frankish rulers would periodically attempt to revive Carolingian glory, but none would achieve imperial coronation until Napoleon Bonaparte in 1804—under dramatically different circumstances. The memory of Carolingian unity would nonetheless serve as both inspiration and justification for later attempts at European domination, from Charles V to Napoleon to the European Union.

Conclusion: The Accidental Birth of Modern Europe

The fragmentation of the Carolingian Empire represents one of history’s great unintended consequences—a process meant to preserve family power that instead created the foundations of modern European nations. The partible inheritance traditions of the Franks, intended to provide for all heirs, ultimately weakened the dynasty and allowed regional identities to crystallize into separate political entities.

The events of 875 in particular demonstrate how historical turning points often emerge from immediate political calculations rather than long-term planning. Charles the Bald’s opportunistic dash to Rome, Pope John VIII’s decision to crown him, Louis the German’s frustrated response—these moments of individual action within a collapsing system created path dependencies that would shape European history for a millennium.

The Carolingian Empire’s dissolution reminds us that large political structures are often more fragile than they appear, that inheritance systems can have unintended consequences, and that the relationship between symbolic authority and practical power is always complex. From the fragmentation of this first European Union emerged the diverse political landscape that would both enrich and bedevil the continent for centuries to come.