The Middle East, 777 to 766 BCE: Turbulence and Transition in Assyria

The Treaty of Verdun (843) and the Division of the Carolingian Empire

Following the death of Emperor Louis the Pious in 840, his eldest son, Lothair I, asserts his claim to overlordship over his brothers' kingdoms and supports his nephew Pepin II’s claim to Aquitaine. However, his brothers, Louis the German and Charles the Bald, reject his authority, leading to civil war among Charlemagne’s grandsons.

The Civil War and the Battle of Fontenay (841)

• Lothair I faces a major defeat at the Battle of Fontenay (841) at the hands of Louis the German and Charles the Bald, who form an alliance against him.
• Their alliance is sealed with the Oath of Strasbourg (842), a key historical document written in both Old French and Old High German, symbolizing the growing linguistic and cultural divide between the eastern and western realms.

The Treaty of Verdun (843): A Formal Division

With his military position weakened, Lothair agrees to negotiate, leading to the Treaty of Verdun (843), which permanently divides the Carolingian Empire among the three surviving sons of Louis the Pious:

• Louis the German receives the East Frankish Kingdom (East Francia), encompassing the lands of German-speaking peoples:
  • Saxony, Eastern Francia, Alemannia, Bavaria, and Carinthia
  • Frankfurt-am-Main becomes the capital of East Francia
• Charles the Bald receives the West Frankish Kingdom (West Francia), comprising French-speaking territories:
  • Western Francia, Aquitaine, Gascony, Brittany, and the Spanish Marches
  • This kingdom evolves into medieval France
• Lothair I retains Middle Francia, the imperial title, and control over:
  • Italy, Provence, Burgundy, and Lotharingia (Lorraine)
  • However, Middle Francia proves politically fragile and will be partitioned further after Lothair’s death in 855.

The Frankish Tradition of Partible Inheritance

The Treaty of Verdun is often interpreted as the beginning of the Carolingian Empire’s decline, but it actually reflects the Frankish adherence to the Germanic tradition of partible inheritance, rather than primogeniture(inheritance by the eldest son).

• Unlike later medieval monarchies that favored single-heir succession, the Franks divided their realms among all male heirs, ensuring that each son received a kingdom rather than ruling as a vassal.
• This tradition continued to fragment the Carolingian realm, leading to the eventual emergence of the distinct kingdoms of France, Germany, and Italy.

Legacy of the Treaty of Verdun

The Treaty of Verdun is one of the most consequential agreements in European history, as it:

• Sets the foundation for modern France and Germany by establishing the linguistic and political divide between the French-speaking West and German-speaking East.
• Marks the beginning of the Holy Roman Empire, as the imperial title becomes linked to Italy rather than Francia.
• Prefigures the dissolution of Charlemagne’s empire, as further partitions and dynastic struggles weaken centralized rule.

While Charlemagne’s vision of a unified Christian empire ultimately proves unsustainable, the Treaty of Verdun shapes the political map of medieval Europe, influencing its kingdoms, conflicts, and cultures for centuries to come.

The Final Partition of the Carolingian Empire and the Outbreak of Civil War (839–840)

Throughout his long reign, Louis the Pious seeks to divide his empire fairly among his sons, adhering to Frankish traditions of partible inheritance as outlined in Salic Law. However, his decision to grant land to his youngest son, Charles the Bald, born from his second marriage to Judith of Bavaria, sparks decades of civil war among his older sons.

The Final Partition of 839: The Division at Worms

Following his vindicating victory over his last rebellious son, Louis the German, in 839, Emperor Louis the Pious divides his empire for the last time at Worms on May 30, 839:

• Lothair I → Retains Italy and the imperial title, along with all the other lands of the east, consolidating his claim as primary ruler of the empire.
• Charles the Bald → Receives all the lands of the west, ensuring a powerful Frankish kingdom that will later evolve into France.
• Louis the German → Left with only Bavaria, significantly reducing his authority.
• Pepin II of Aquitaine (son of the late Pepin I) → Excluded from the inheritance, fueling his discontent.

This arrangement favors Charles and Lothair, sidelining Louis the German and Pepin II, setting the stage for another civil war upon Louis the Pious’ death in 840.

The Death of Louis the Pious and the Civil War (840–843)

On June 20, 840, Louis the Pious dies, and almost immediately, Lothair I attempts to assert full imperial control, violating the agreements of Worms (839).

• On July 24, 840, in Strasbourg, Lothair declares his imperium over all Frankish lands, claiming overlordship over his brothers.
• He allies with his disinherited nephew, Pepin II of Aquitaine, and together they invade the Loire Valley, launching a campaign against Charles the Bald.

The Fracturing of the Empire: Divided Loyalties

The Carolingian nobility is divided in allegiance, particularly in Burgundy, where counts split between Charles and Lothair:

Lothair’s Supporters

• Ermenaud III of Auxerre
• Arnoul of Sens
• Audri of Autun
• Girard II, Count of Paris (Lothair’s brother-in-law)

Charles’ Supporters

• Guerin of Provence
• Aubert of Avallon

The War’s Outcome: The Treaty of Verdun (843)

The war continues until Charles the Bald and Louis the German defeat Lothair at the Battle of Fontenay (841) and solidify their alliance with the Oaths of Strasbourg (842). This culminates in the Treaty of Verdun (843), which permanently divides the Carolingian Empire into three distinct kingdoms:

• West Francia → Charles the Bald (precursor to France).
• Middle Francia → Lothair I, including the imperial title, but his kingdom will later fracture.
• East Francia → Louis the German (precursor to Germany).

Legacy of the 839 Partition and Civil War

• The dream of a unified Carolingian Empire collapses, marking the beginning of medieval Europe’s political map.
• The Frankish kingdoms begin evolving into separate entities, leading to the future emergence of France and Germany.
• Lothair’s imperial ambitions fail, and his Middle Frankish Kingdom proves unstable, setting the stage for further fragmentation.

Thus, the final partition of Louis the Pious in 839 directly leads to the division of Charlemagne’s empire, shaping the medieval European world for centuries to come.

The Carolingian Civil War: The Alliance of Charles the Bald and Louis the German (841)

As the conflict between Lothair I and his brothers intensifies, Charles the Bald and Louis the German strengthen their alliance against Lothair, culminating in the pivotal Battle of Fontenay (841).

The Burgundian Reinforcements for Charles (March 841)

• Many Burgundian nobles, disillusioned with Lothair’s imperial ambitions, remain loyal to Charles the Bald.
• In March 841, Guerin of Provence, a prominent supporter of Charles, leads the Burgundian forces to join him in preparation for a decisive confrontation.

The Meeting of the Armies at Châlons-sur-Marne (May 841)

• By May 841, Louis of Bavaria (Louis the German) marches westward with his Bavarian troops and meets Charles’s army at Châlons-sur-Marne.
• This meeting formalizes the military alliance between the two brothers against Lothair I and Pepin II of Aquitaine.

Toward the Battle of Fontenay (June 841)

• This Frankish civil war reaches its climax at the Battle of Fontenay (June 25, 841), where Charles and Louis decisively defeat Lothair.
• Their victory solidifies their hold over their respective kingdoms and leads to the Treaty of Verdun (843), which permanently divides the Carolingian Empire.

Significance of the 841 Alliance

• The meeting at Châlons-sur-Marne marks the final preparations for the decisive battle.
• The Burgundian nobles play a crucial role in supporting Charles, reinforcing the political fragmentation of the empire.
• The unity between Charles and Louis directly leads to the long-term division of Francia into what will become France and Germany.

Thus, the March and May 841 events are critical steps leading to the Battle of Fontenay, the Treaty of Verdun, and the permanent reshaping of medieval Europe.

Pepin II of Aquitaine Joins Lothair I at Auxerre (June 841)

As the Carolignian civil war intensifies, Pepin II of Aquitaine—the grandson of Louis the Pious and son of the late Pepin I—formally aligns with Lothair I in June 841, meeting him at Auxerre.

Strategic Importance of the Alliance

• Pepin II had been sidelined by his grandfather, Louis the Pious, in 839, when the emperor granted Aquitaine to Charles the Bald, effectively disinheriting him.
• With the empire now fractured by war, Pepin sees an opportunity to reassert his claim to Aquitaine by siding with Lothair, who seeks to maintain his imperial authority over his brothers.
• Auxerre, located in Burgundy, is a strategic meeting point, allowing Pepin’s forces to reinforce Lothair’s army before the upcoming Battle of Fontenoy (June 25, 841).

The Outcome

• Despite their combined forces, Lothair and Pepin suffer a crushing defeat at Fontenoy, leading to Lothair’s retreat to Aachen.
• Pepin continues to fight for his claim to Aquitaine, but after the Treaty of Verdun (843), Charles the Bald is officially recognized as King of West Francia, permanently reducing Pepin to the status of a regional rebel.

This moment marks Pepin’s last chance to reclaim his kingdom through imperial backing, but his defeat alongside Lothair ensures that his struggle will be confined to local conflicts rather than the larger imperial contest.

The Battle of Fontenoy (June 25, 841): The Decisive Clash of the Carolingian Civil War

The Battle of Fontenoy, fought on June 25, 841, marks the culmination of the Carolingian civil war, as Lothair I and Pepin II of Aquitaine face off against Charles the Bald and Louis the German in one of the bloodiest battles of the era.

Early Success for Lothair and Pepin

• Lothair and Pepin initiate the battle, launching a fierce assault on their brothers’ forces.
• Initially, Lothair gains the upper hand, pushing back the army of Louis the German.
• Meanwhile, Pepin II’s contingent steadily forces Charles the Bald’s army into retreat.

The Arrival of Guerin of Provence and the Shift in Momentum

• At the crucial moment, Guerin of Provence arrives with his reinforcements, consisting of a battle-hardened army from Provence.
• His forces turn the tide in favor of Charles, particularly against Lothair’s army, which begins to falter under the combined assault of Louis the German and the Provençals.

Bernard of Septimania’s Entry Secures Victory

• As the battle reaches its climax, Bernard of Septimania enters the conflict on the side of Charles, tipping the scales decisively.
• With Bernard’s reinforcements, the battle becomes a rout, and Lothair’s forces are driven from the field.

Casualties and Aftermath

• The battle is incredibly costly, with an estimated 40,000 dead, making it one of the most devastating battles of the Carolingian period.
• Notable casualties include:
  • Gerard of Auvergne, a close ally of Charles, falls in battle.
  • Ricwin of Nantes, another loyal supporter, also dies fighting alongside Charles.

Lothair’s Flight to Aachen

• Despite his personal bravery, Lothair is defeated and forced to flee to Aachen, his imperial capital.
• His retreat marks the end of his attempt to dominate the empire, as Charles and Louis solidify their control.

Consequences of the Battle

• The defeat of Lothair at Fontenoy paves the way for the Treaty of Verdun (843), which permanently divides the Carolingian Empire.
• Charles the Bald and Louis the German consolidate their respective kingdoms, while Lothair, though still emperor, is left politically weakened.
• The massive loss of life and destruction further accelerates the fragmentation of the empire, ensuring that Charlemagne’s dream of a unified Frankish realm will never be restored.

The Battle of Fontenoy, though a civil war among brothers, reshapes the political landscape of medieval Europe, setting the stage for the eventual formation of France and Germany.

Breton Defiance and Nominoe’s Raids Against Charles the Bald (843–844)

By 843, the initially amicable relationship between Nominoe, governor of Brittany, and Charles the Bald begins to break down. Nominoe, once a loyal Carolingian appointee, increasingly asserts Breton independence, leading to open conflict.

Charles’ Failed Campaign Against Brittany (November 843)

• In an attempt to compel Breton submission, Charles the Bald marches as far as Rennes in November 843.
• Despite his efforts, he fails to bring Brittany under direct Frankish control.
• The Bretons refuse to yield, and Charles is unable to achieve a decisive victory.

Breton Troops and the Conflict in Neustria (844)

• In Neustria, Breton forces fight under Lambert II of Nantes, one of Charles’ enemies.
• This signals that Nominoe is actively siding against Charles, supporting Frankish rebels as well as conducting his own military campaigns.

Nominoe’s Raid into Maine (June 844)

• While Charles is besieging Toulouse in June 844, ...

...

• Nominoe seizes the opportunity to raid into Maine, a key region in western Francia.
• Breton forces plunder the territory, demonstrating that Nominoe is no longer acting as a loyal vassal but rather as an independent ruler expanding his influence into Frankish lands.

The Beginning of Breton Independence

• These actions mark the start of a full-scale Breton revolt against Carolingian authority.
• Nominoe will continue his military campaigns, leading to further Frankish-Breton conflicts and the eventual establishment of Brittany as an autonomous entity.
• Charles the Bald, already facing Viking incursions and internal revolts, struggles to maintain control over the region, foreshadowing Brittany’s long-term resistance to Frankish rule.

The events of 843–844 solidify Nominoe’s position as the de facto ruler of an independent Brittany, setting the stage for continued Breton defiance and expansion.

The Synod of Metz (October 844) and the Carolingian Attempt to Reassert Authority

By October 844, Charles the Bald seeks to restore his authority over rebellious vassals who are challenging his rule in Brittany, Neustria, and Aquitaine. The bishops at the Synod of Metz, presided over by Charles' uncle, Drogo of Metz, issue a formal decree aimed at compelling:

• Nominoe, ruler of Brittany,
• Lambert II of Nantes, and
• Pepin II of Aquitaine

to renew their fealty to Charles or face military consequences.

The Church’s Role in Securing Royal Authority

• The bishops act as political agents of the Carolingian monarchy, reinforcing the idea that revolt against the king is not only treasonous but also a violation of Christian duty.
• Drogo of Metz, a close ally of Charles, uses the Church’s moral authority to pressure the rebels into submission.
• The synod’s orders serve as both a warning and a justification for an upcoming military campaign should the rebels refuse to comply.

Nominoe, Lambert, and Pepin’s Response

• Nominoe continues his raids into Frankish lands, showing no sign of submission.
• Lambert II of Nantes remains aligned with Breton forces, fighting against Charles' supporters in Neustria.
• Pepin II of Aquitaine, the disinherited grandson of Louis the Pious, refuses to relinquish his claim and continues his war for control over Aquitaine.

Consequences and Escalation of Conflict

• The failure of the Synod of Metz to secure peace leads directly to Charles’ military campaigns against Brittany and Neustria in the following years.
• The rebellion of Nominoe and Lambert culminates in Charles' disastrous defeat at the Battle of Ballon (845), where Breton independence is effectively cemented.
• Pepin II’s resistance in Aquitaine continues, ensuring that Charles must fight on multiple fronts while also contending with Viking incursions into West Francia.

Despite the Church’s involvement in the conflict, the Synod of Metz fails to subdue the rebellious lords, setting the stage for prolonged wars that will further fragment the Carolingian realm.