The Normans were a people who in the 10th and 11th centuries gave their name to Normandy, a region in France. They were descended from Norse ("Norman" comes from "Norseman") raiders and pirates from Denmark, Iceland, and Norway who, under their leader Rollo, agreed to swear fealty to King Charles III of West Francia. Through generations of assimilation and mixing with the native Frankish and Roman-Gaulish populations, their descendants gradually merged with the Carolingian-based cultures of West Francia.The cultural and ethnic identity of the Normans emerged initially in the first half of the 10th century, and continued to evolve over the succeeding centuries.

The Norman dynasty had a major political, cultural, and military impact on medieval Europe. They adopted the Gallo-Romance language of the Frankish land they settled, their dialect becoming known as Norman, Normaund, or Norman French, an important literary language. The Duchy of Normandy, formed by treaty with the French crown, was a great fief of medieval France that under Richard I of Normandy became a cohesive and formidable principality. The Normans are noted both for their culture and for their significant military accomplishments.. Norman adventurers founded the Kingdom of Sicily under Roger II after conquering southern Italy from the Saracens and Byzantines. An expedition on behalf of their duke, William the Conqueror, led to the Norman conquest of England at the Battle of Hastings in 1066.

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