William Family History

English (of Norman origin): from the Middle English personal name William, Willam, Willem, an Old Picard and Norman French form of ancient Germanic Willihelm, composed of the elements wil- ‘will, desire’ + helm- ‘helmet, protection’. This Norman personal name became widely used in England, Scotland, and Wales after the Conquest, mainly no doubt in honor of the Conqueror himself.

By the 13th century, it had already become the most popular personal name in England. A Parisian form of the name Guillaume was also sometimes used (see Gillam), which in medieval Wales was adopted as Gwilym (see Gwilliam).

The Americanized form of the name is a translation into English from the French Guillaume.