William Willoughby, 1st Baron Willoughby of Parham (c.1515 – 1570), English baron and nephew of the above
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William Willoughby, 11th Baron Willoughby de Eresby (1482-1526), father of Katherine Willoughby and the largest landowner in Lincolnshire, England
William Shakespeare | William Laud | William Blake | William | William III of England | William Morris | William McKinley | William Howard Taft | William Ewart Gladstone | William the Conqueror | William S. Burroughs | William Shatner | William Faulkner | William Randolph Hearst | William Wordsworth | William Tecumseh Sherman | William Hogarth | Prince William, Duke of Cambridge | William Penn | William Jennings Bryan | William Gibson | William Wilberforce | William James | William Makepeace Thackeray | Fort William | William Hanna | William Hague | William III | William Hurt | William Walton |
Willoughby v. Stever was a 1973 American legal decision in a case brought by evangelist William Willoughby against the National Science Foundation director H. Guyford Stever and the Board of Regents of the University of Colorado for using taxpayer money to fund textbooks developed by the Biological Sciences Curriculum Study (BSCS) because they included evolution instruction.