Europe's borders in the Middle Ages were created by one man, and he wasn't even born in the Middle Ages, nor was he Christian. It was Emperor Diocletian, who ruled Rome from 284 to 305. His reforms that chained tenant farmers to land created the blueprint for feudalism. He split the empire, which established the East-West divide. Lastly, his shift from static Roman legions to mobile armies set the stage for the warrior kingdoms that would dominate the early Middle Ages. Today, new genetic analysis of skeletal and tooth remains is revolutionizing how we understand this transformation—a high-status woman buried around 550 in Britain was born in Norway according to her childhood tooth enamel, proving the "barbarian invasions" were actually century-long migrations averaging just three miles per day. Today's guest is John Haywood, author of The Making of the Middle Ages: An Atlas of Europe. We discuss how Europe from 500-700 was ruled by warrior kingdoms with mobile courts that constantly traveled—only shifting to fixed courts and proper imperial administration after Charlemagne established counties, libraries, copyists, and the emporia trading centers where workshops and markets flourished. Haywood also explains how Ravenna's independence from Byzantium portended the rise of papal power, why towns collapsed from Roman populations of thousands to mere hundreds unless a bishop resided there, and how the density of churches and monasteries north of the Alps exploded between 600 and 1200 as the Catholic Church consolidated power across formerly pagan Germanic territories.