Roman general Flavius Aetius suppresses the Bagaudae in Armorica (Gaul) and …

The Romano-British Migration to Armorica and the Birth of Brittany

As the Western Roman Empire collapses, waves of Romano-British immigrants flee Britain, crossing the English Channel to settle in Armorica (modern-day Brittany). This migration, which had begun earlier in the fifth century, accelerates dramatically in response to the increasing pressure of:

• Anglo-Saxon raids and settlements in eastern and southern Britain, displacing native Britons.
• Scoti (Irish) incursions into western Britain, including Wales and Cornwall.
• The general breakdown of Roman authority in Britain following the withdrawal of Roman legions (c. 410 CE).

The Formation of a British Identity in Armorica

• The Romano-British immigrants, known as Britons or Bretons, settle primarily on the Armorican Peninsula, where they establish permanent communities.
• These migrants bring with them their language (a Brythonic Celtic dialect), Christianity, and Romano-British traditions, heavily influencing local culture.
• Over time, the Armorican Peninsula becomes known as "Brittany" (Bretagne in French), a reflection of its British origins.

Evidence of Cultural and Linguistic Ties

The connection between Britain and Brittany is evident in:

• Place names – Many regions in Brittany bear names linked to Cornwall and Devon, such as Domnonée (related to Dumnonia in Britain) and Cornouaille (Cornwall).
• Language – The Breton language, still spoken today, remains closely related to Cornish and Welsh.
• Religious and monastic ties – Many early Christian saints venerated in Brittany (e.g., Saint Samson, Saint Malo, and Saint Gildas) were originally from Britain, reinforcing the region’s shared heritage.

Armorica Transformed into Brittany

By the end of the fifth century, the influx of Britons has permanently reshaped Armorica, turning it into a distinct Celtic region within post-Roman Gaul. While surrounded by Frankish and Gallo-Roman territories, Brittany retains its cultural and political independence, developing alongside, but separate from, the Frankish Kingdom.

This migration is one of the most significant cultural shifts of the period, ensuring that Celtic Britain continues to influence the continent, even as much of Britain itself falls under Anglo-Saxon control.

Frankish Rule in Eastern Brittany and Breton Raids (6th Century CE)

During the sixth century, the Franks maintain control over eastern Brittany, integrating it into their expanding kingdom. However, they must continually defend their territory against Breton raids, as the Bretons establish heavily populated settlements in the western part of the peninsula.

1. Frankish Control of Eastern Brittany

• Following Clovis I’s expansion, the eastern part of Brittany comes under Frankish rule, particularly along the borderlands near Rennes, Nantes, and Vannes.
• The Franks establish military outposts and administrative centers, securing nominal control over the region.
• Frankish influence is strongest in the bishoprics of eastern Brittany, where the Church plays a key role in governance.

Chilperic I’s Breton Campaign Against Waroch II (578 CE)

In 578 CE, Chilperic I of Neustria launches a military campaign against Waroch II, the ruler of the Veneti (Vanetais), a powerful Breton leader along the Vilaine River. This conflict is part of the ongoing Frankish struggle to maintain dominance over eastern Brittany, where Breton lords frequently resist Frankish control.

1. Composition of the Frankish Army

Chilperic assembles a diverse army, drawing forces from:

• Poitou
• Touraine
• Anjou
• Maine
• Bayeux

Notably, the men from Bayeux (Baiocassenses) are Saxons, likely descended from earlier Saxon settlers in Neustria. These Saxon warriors play a significant role in the battle.

2. The Battle Against the Bretons

• The Frankish and Breton armies engage in battle for three days, with heavy fighting along the Vilaine River.
• The Bretons decisively rout the Saxons from Bayeux, highlighting the ferocity of Breton resistance.
• After prolonged fighting, Waroch II submits, recognizing Chilperic’s authority.

3. Terms of Waroch II’s Surrender

• Waroch does homage to Chilperic for Vannes, acknowledging Frankish suzerainty.
• He sends his son as a hostage, ensuring his loyalty.
• He agrees to pay an annual tribute, securing peace on Frankish terms.

4. Waroch’s Subsequent Rebellion and Frankish Control Over Brittany

• Despite swearing loyalty, Waroch later breaks his oath, continuing Breton resistance.
• However, Chilperic’s dominance over the Bretons remains relatively secure.
• The poet Venantius Fortunatus celebrates Chilperic’s victory in a poem, demonstrating the significance of the campaign in Frankish propaganda.

Conclusion: Frankish Struggles to Subdue Brittany

The 578 campaign is part of the larger Merovingian effort to control Brittany, a region that remains semi-independent and rebellious. Chilperic’s temporary success against Waroch II shows the strength of Frankish influence, but the Bretons will continue to resist, making Brittany one of the most difficult territories for the Franks to govern.

The Peace Agreement Between Charles the Bald and Nominoe (846): The Recognition of Breton Autonomy

Following his defeat at the Battle of Ballon (845), Charles the Bald marches on Brittany again in the summer of 846. However, instead of engaging in further military action, he negotiates a peace settlement with Nominoe, the de facto ruler of Brittany.

The Terms of the Peace Agreement

While the exact details of the peace settlement remain uncertain, historical sources suggest:

• Nominoe and Charles exchange oaths, likely formalizing Breton autonomy under nominal Frankish overlordship.
• Prudentius of Troyes refers to Nominoe as "Duke" (dux) of the Bretons, possibly indicating that Charles officially recognizes Nominoe as ruler in exchange for his acknowledgment of Frankish suzerainty.
• As part of the arrangement, Nominoe demands the removal of Lambert II of Nantes, a Frankish noble who had been an opponent of Breton interests.
• Charles removes Lambert from Nantes and relocates him to another region, weakening his influence over Breton affairs.

Significance of the 846 Agreement

• While Charles nominally retains overlordship, this agreement effectively solidifies Nominoe’s independent rule over Brittany.
• By securing Lambert’s removal, Nominoe eliminates a powerful Frankish rival, further consolidating his authority.
• This diplomatic resolution temporarily ends the Frankish-Breton conflict, though tensions will later resurface as Breton expansion into Frankish territory continues.

Aftermath and the Path Toward Breton Sovereignty

• In the following years, Nominoe continues to strengthen Brittany, even launching further campaigns into Frankish lands.
• By 850, Brittany will no longer be merely a semi-autonomous duchy but will begin functioning as a fully independent entity, defying Carolingian control.

Thus, while the 846 settlement represents a temporary peace, it is a major step toward Breton independence, marking the beginning of Brittany’s long resistance against Frankish rule.

Nominoe’s Continued Raids in Neustria and Charles the Bald’s Response (849)

Despite the orders from the Council of Meerssen (847) demanding that Nominoe of Brittany and Pepin II of Aquitaine cease their attacks on Charles the Bald, both rulers persist in their campaigns, likely with support from Emperor Lothair I.

Nominoe’s Opportunistic Raids in 849

• Nominoe, likely funded by Lothair, refuses to desist and continues his raids into Neustria.
• In the spring of 849, while Charles is occupied in Aquitaine, Nominoe takes advantage of his absence to raid Neustria once again.
• When Charles returns to the region in the fall, Nominoe launches a second campaign, further demonstrating his independent power.

The Breton Invasion of Anjou and the Restoration of Lambert in Nantes

• Nominoe invades Anjou, expanding Breton control deeper into Frankish territory.
• In response, Charles reestablishes Lambert II of Nantes in his former position, reinforcing Frankish presence on the Breton border.
• This move signals Charles’ renewed attempt to curb Breton expansion, using loyal Frankish nobles to counter Nominoe’s influence.

The Ongoing Carolingian-Breton Conflict

• Nominoe’s continued defiance shows that he is no longer acting as a mere Carolingian vassal but is instead building an autonomous Breton state.
• The failure of Charles to permanently subdue Brittany foreshadows further conflicts, culminating in Nominoe’s victories over Frankish forces in the early 850s.
• Lothair’s possible financial support for Nominoe and Pepin II suggests that he still seeks to weaken Charles, using these regional rulers as proxy forces.

By 849, Brittany is no longer just a rebellious province, but a rising power actively expanding into Carolingian lands, setting the stage for further Breton-Franconian warfare.

The Breton-Frankish Conflict and the Renewed Alliance of Lambert and Nominoe (850)

By 850, the Breton resistance against Charles the Bald intensifies, as Lambert II of Nantes and his brother Warnar renew their alliance with Nominoe, ruler of Brittany. Their combined forces launch devastating raids into Maine, described by the Chronicon Fontanellense as carried out "with unspeakable fury."

Charles the Bald’s Campaign in Rennes and Nantes (August 850)

• In August 850, Charles marches on Rennes in another attempt to subdue Brittany, but once again avoids direct combat.
• Instead of engaging in battle, he installs Frankish garrisons in Rennes and Nantes, hoping to maintain control through military occupation rather than outright conquest.