Which leader of the Franks unified all Christian lands?

The leader of the Franks who is often credited with unifying all Christian lands is Charlemagne, also known as Charles the Great. He ruled from 768 to 814 and expanded the Frankish empire through a series of military conquests, spreading Christianity throughout his territories. In 800, he was crowned Emperor of the Romans by Pope Leo III, symbolizing the fusion of Roman, Christian, and Germanic elements in his rule. Charlemagne's efforts laid the foundation for what would later become the Holy Roman Empire.