Guillaume

French

form of William, meaning "From the Germanic name Willahelm, which was composed of the elements wil "will, desire" and helm "helmet, protection". Saint William of Gellone was an 8th-century cousin of Charlemagne who became a monk. The name was common among the Normans, and it became extremely popular in England after William the Conqueror was recognized as the first Norman king of England in the 11th century. It was later borne by three other English kings, as well as rulers of Scotland, Sicily (of Norman origin), the Netherlands and Prussia."