Overview
William is a masculine given name of Germanic origin. It became very popular in the English language after the Norman conquest of England in 1066, and remained so throughout the Middle Ages and into the modern era. It is sometimes abbreviated "Wm." Shortened familiar versions in English include Will, Wills, Willy, Willie, Liam, Bill, and Billy. A common Irish form is Liam. Scottish diminutives include Wull, Willie or Wullie (as in Oor Wullie or the play Douglas). Female forms are Willa, Willemina, Wilma and Wilhelmina.
Etymology
William is related to the German given name Wilhelm. Both ultimately descend from Proto-Germanic *Wiljahelmaz, with a direct cognate also in the Old Norse name Vilhjalmr and a West Germanic borrowing into Medieval Latin Willelmus. The Proto-Germanic name is a compound of *wiljô "will, wish, desire" and *helmaz "helm, helmet".
By regular sound change, Proto-Germanic *Wiljahelmaz should have also descended into English as *Wilhelm, but this latter form is unattested in written English of any period; the Anglo-Saxon Chronicle refers to William the Conqueror as Willelm, a back-formation from the Medieval Latin variant. The form William is a back-borrowing from Old Norman Williame, a specifically northern Norman reflex of Medieval Latin Willelmus (compare the Central French cognate Guillaume). The development of the name's northern Norman form can be traced in the different versions of the name appearing in Wace's Roman de Rou.
The first well-known bearer of the name was Charlemagne's cousin William of Gellone (755–812). This William is immortalized in the Chanson de Guillaume, and the esteem in which he was held may account for the name's subsequent popularity among European nobility.
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