william

William is a masculine given name of Germanic origin. It derives from the elements wil (desire, will) and helm (helmet, protection), forming a name often interpreted as "resolute protector" or "will helmet."

The name spread widely in medieval Europe after the Norman Conquest, and William the Conqueror, Duke of Normandy and King of England (reigned 1066–1087), helped popularize it in England and beyond. Over the following centuries, William became common among royalty and clergy, and later among the general population.

Variants and derivatives include Wilhelm (German), Guillaume (French), Willem (Dutch), Guillermo (Spanish), and Guglielmo (Italian). Diminutives such as Will, Willy, Bill, and Billy are widely used in English. The surname forms Williamson and Williams are patronymic derives from the given name.

Notable people named William include the playwright William Shakespeare, the poet William Wordsworth, the novelist William Faulkner, and the Scottish knight William Wallace. In politics, William III of England (William of Orange) and Prince William, Duke of Cambridge, are well known. In fiction, the name appears frequently as well.

Today, William remains a common, traditional given name in many English-speaking countries and elsewhere, valued for its historical associations and enduring versatility.