Dagobert I

Dagobert I took Austrasia in 623, still in his late teens or early twenties, then added Neustria and Burgundy six years later to command the Frankish kingdoms whole. For a decade and a half he governed with the kind of active control his successors would never recover: he led, he decided, he mattered. When he died on 19 January 639, he was laid in the royal tombs at Saint-Denis — the first Frankish king given that honor. The mayors of the palace, until then administrators, began their quiet eclipse of the throne, and the Merovingian line drifted into irrelevance under his children's names.