Charlemagne & Carloman Crowned: When the Franks Tried Double Kings

On October 9, 768, medieval Europe tried an experiment no kingdom should ever repeat: two kings at the same time. When Pepin the Short (yes, that was literally his name) died, his sons Charlemagne and Carloman I were crowned joint rulers of the Frankish kingdom.

Spoiler: it went exactly how every group project in school goes when you force two brothers to “share power.” One did all the work (Charlemagne). The other sulked until fate conveniently took him out of the story (Carloman). And this sibling drama ended up shaping centuries of European history.

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When their father King Pepin the Short died, custom dictated that the realm be divided equally among his sons. This system, known as partible inheritance, turned kingdoms into messy pizzas sliced down the middle.

In theory, this split was “fair.” In practice? It created simmering tension between the two brothers, with Charlemagne drawing luckier cards while Carloman seethed.

In a kingdom with such a divide, cooperation was key. But “cooperation” was not in the Carloman rulebook. Historians tell us that the brothers’ cold war was obvious from almost day one:

It was like a medieval reality TV show: The Real Kings of the Franks, starring one hardworking ruler and one professional grumper.

Then, in 771, Carloman died at just 20 years old. Sudden illness? Stress? Or the medieval equivalent of “somebody slipped something funny in his ale”? Historians don’t know for sure, but the outcome was earth-shaking:

Without Carloman’s sudden exit, Charlemagne might never have become the ruler of Western Europe. Instead, within three decades he conquered the Lombards, Christianized the Saxons (violently), and in 800 CE, Pope Leo III crowned him Emperor of the Romans.

In other words: Carloman’s death was the pivot that launched Charlemagne from “annoyed big brother” to “Charles the Great.”

October 9, 768 represents the moment Europe almost split permanently. If both brothers had lived longer, Frankland may have fractured, leaving no “Holy Roman Empire” to dominate medieval history textbooks.

This is Grade-A medieval sibling rivalry. Betrayals, passive aggression, divided kingdoms, and sudden death. It’s basically Succession, but with swords, bishops, and way more beards.

This teaches the timeless truth: sharing power rarely works when egos are involved. Whether it’s medieval Franks or your last group project, someone always ends up doing all the work, and somebody else bails.

Charlemagne got lucky, yes — but he also knew how to wield power, ally with the Pope, and seize chances when others fell away. Carloman gets remembered mostly because he wasn’t Charlemagne.

On October 9, 768, the Franks crowned two kings. By 771, only one king remained. And thanks to that twist, medieval Europe had the empire-building giant we still call Charlemagne the Great.

Pepin the Short was the first Carolingian king of the Franks. Upon his death, Frankish custom required dividing the kingdom among his sons, Charlemagne and Carloman. This is why they both became kings on October 9, 768.

Historians believe personality differences, unequal territorial inheritance, and political tension made cooperation impossible. Charlemagne was decisive and ambitious, while Carloman was hesitant and resistant to his brother’s plans.

Carloman died suddenly in 771 at just 20 years old. The exact cause is uncertain—most likely illness—but his unexpected death ended the co-kingship and allowed Charlemagne to take full control.

If Carloman had ruled longer, historians believe the Frankish kingdom may have fractured permanently. Charlemagne’s later unification of Western Europe—and his eventual coronation as Emperor in 800—may never have happened.

Charlemagne created the foundations of medieval Europe by uniting much of Western Europe, promoting Christianity, restoring learning, and reviving imperial tradition through his coronation as “Emperor of the Romans.”

Because history isn’t boring—it’s bananas.