The transformation began in the early 10th century when the Viking chieftain Rollo struck a pivotal agreement with the Frankish king Charles the Simple. In exchange for loyalty and defense against future Viking raids, Rollo was granted land in what would become Normandy. Over time, these Norse settlers adopted the local language, embraced Christianity, and intermarried with the Frankish population. Yet they never lost their boldness, their military prowess, or their ambition to expand beyond the borders of their new homeland. Within a few generations, the Normans had become a force to be reckoned with—not just in France, but across Europe and even the Mediterranean.