Emperor Wuzong, in an attempt to return…

Wujie Khan's forces and Tang's border defense forces had subsequently come into open combat, even though both sides have continued negotiations.

In 843, the Tang general Liu Mian launchesa surprise attack against Wujie Khan, led by his officer Shi Xiong, who crushes Wujie Khan's forces and rescues Princess Taihe.

Wujie Khan flees, and subsequently, the Uyghur remnants will create only minor nuisances for Tang and no longer pose a major threat.

The Tang Chinese inflict a devastating defeat upon the Uyghur Qaghan's forces on February 13, 843 at "Kill the Foreigners" Mountain, but the Yenisei Kyrgyz, rather than replace the Uyghurs as the lords of Mongolia, continue to live in their traditional homeland and exist as they had for centuries.

The defeat and collapse of the Uyghur Khaganate triggers a massive migration of Uyghurs from Mongolia into Turfan, Kumul, and Gansu where they found the Kingdom of Qocho and, in around 894, the Ganzhou Uyghur Kingdom.

The most long-term result of the fall of Amorium is in the religious rather than in the military sphere.

Iconoclasm was supposed to bring divine favor and assure military victory, but neither the army's weaknesses nor the reported treachery of Boiditzes could detract from the fact of the disastrous defeat.

A little over a year after Theophilos's death, on March 11, 843, a synod restores the veneration of icons, and iconoclasm is declared heretical, but a conciliatory ecclesiastical policy is directed towards the Iconoclasts.

Also beginning in 843, campaigns undertaken against the Slavs in Greece and against the Arabs in Asia Minor, the Aegean, and the Nile Delta meet with some success.

New measures to confront the Cretan threat in 842 after the death of Theophilos are undertaken by the new imperial regime:a new maritime theme, that of the Aegean Sea, is established in 843 to better deal with the Saracen raids, and another expedition to recover Crete is launched under the personal leadership of the powerful logothetes and regent Theoktistos.

It succeeds in occupying much of the island, but Theoktistos has to abandon the army due to political intrigues in Constantinople, and the troops left behind are slaughtered by the Arabs.

The Archbishopric of Hamburg, created in 843, is charged with the mission of Christianizing Scandinavia.

The Saxon nobilies themselves disarm the Stellinga movement with a brutal action in 843.

Kenneth MacAlpin unites the Scots and Picts to form a kingdom in central Scotland, ruling as Kenneth I. Kenneth's origins are uncertain, as are his ties, if any, to previous kings of the Picts or Dál Riata.

Compared with the many questions on his origins, Kenneth's ascent to power and subsequent reign can be dealt with simply.

Kenneth's rise can be placed in the context of the recent end of the previous dynasty, which had dominated Fortriu for two or four generations.

This followed the death in 839 of king Uen son of Óengus of Fortriu, his brother Bran, Áed mac Boanta "and others almost innumerable" in battle against the Vikings.

The resulting succession crisis seems, if the Pictish Chronicle king-lists have any validity, to have resulted in at least four would-be kings warring for supreme power.

Kenneth's reign is dated from 843, but it is probably not until 848 that he defeated the last of his rivals for power.

The Breton Rebellion and the Battle of Messac (843): The Rise of an Independent Brittany

The Armorican peninsula—modern-day Brittany—had long been inhabited by Gallic tribes, known in Latin as the Armorici, before falling under Roman rule. By the 4th to 7th centuries, waves of Britonnes migrants from Roman Britain arrived, blending with the local population to form the Bretons.

Carolingian Conquest and the Rise of Nominoe

• The Carolingian Empire conquered Brittany between 748 and 799, integrating it into its administrative framework, centering on Rennes, Nantes, and Vannes.
• Despite Frankish efforts, their hold on Brittany remained weak, as local rulers retained autonomy.
• Carolingian technology, culture, and Church structures began influencing Brittany.
• In 831, Emperor Louis the Pious appointed Nominoe, Count of Vannes, as ruler of the Bretons and imperial missus (royal envoy), an attempt to secure loyalty.

Brittany’s Rebellion Against West Francia

• Following the breakup of the Carolingian Empire, Nominoe rebels against the rule of Charles the Bald, seeking to expand Breton autonomy into Frankish lands.
• Charles appoints Renaud as Count of Nantes to secure the border, which angers Lambert II of Nantes, who sees himself as the rightful heir.
• Lambert aligns with Nominoe and his son Erispoe, creating a Frankish-Breton alliance against Charles.

The Battle of Messac (May 24, 843)

• Renaud, believing Nominoe is incapacitated by illness, marches from Nantes to strike a preemptive blowagainst Erispoe’s army near the Vilaine River.
• Erispoe’s forces, caught mid-crossing at Messac, are routed, suffering heavy casualties.

The Arrival of Lambert and the Breton Counterattack

Sources differ on the exact events that follow:

1. Version One (Messac Counterattack):

   • Lambert, having raised troops in Anjou, arrives in time to reinforce Erispoe at Messac.
   • The combined Breton and Frankish rebel army counterattacks, encircling and destroying Renaud’s army.

2. Version Two (Ambush at Blain):

   • Believing he has defeated the Bretons, Renaud withdraws to Blain to rest.
   • Erispoe and Lambert pursue him, launching a surprise attack on resting Frankish forces at the Isac River, massacring them.

Regardless of the version, Renaud is killed, and the Frankish army is annihilated.

Possible Viking Involvement

• A Viking force under Hastein may have joined the Bretons, though some sources suggest they arrived later to raid the battlefield.
• This marks an early instance of Viking-Breton cooperation, foreshadowing future alliances against West Francia.

Aftermath and the Strengthening of Brittany

• Charles the Bald replaces Renaud with Amaury as Count of Nantes.
• Nominoe strengthens Breton independence, laying the foundation for the emergence of a unified Kingdom of Brittany.
• The victory at Messac solidifies Erispoe’s leadership, allowing him to later secure recognition of Breton independence at the Treaty of Angers (851).

The Battle of Messac (843) is a pivotal moment in Breton resistance against Carolingian rule, signaling the decline of Frankish influence and the rise of an independent Brittany.

The Treaty of Verdun (843) and the Formation of West Francia

The Treaty of Verdun, signed in 843, formally divides the Carolingian Empire among the three surviving sons of Louis the Pious, marking the beginning of medieval Europe’s territorial and linguistic divisions.

Charles the Bald and the West Frankish Kingdom

Under the treaty, Charles the Bald, the half-brother of Lothair I and Louis the German, receives West Francia, encompassing the lands of the French-speaking peoples. His kingdom includes:

• Western Francia → The heartland of what will become France.
• Aquitaine → A semi-independent region with strong noble traditions.
• Gascony → A southwestern region known for its Basque influence and military resistance.
• Brittany → A land of Celtic autonomy, only nominally under Frankish rule.
• The Spanish Marches → The buffer zone against Muslim Al-Andalus, including Catalonia.

Significance of the Treaty

• The division reflects the cultural and linguistic split between the French-speaking West and the Germanic East.
• Charles inherits a fragmented kingdom, with regional lords in Aquitaine and Brittany asserting semi-independence.
• The treaty sets the stage for the eventual emergence of France, though West Francia remains politically unstable for centuries.

By awarding Charles the Bald control over the western portion of the empire, the Treaty of Verdun lays the foundation for the medieval French state, while simultaneously weakening Carolingian unity and accelerating the empire’s decline.