William Paulet, 4th Marquess of Winchester (bef. 1560[1] – 4 February 1629) was an English nobleman, the son of William Paulet, 3rd Marquess of Winchester and Anne or Agnes Howard.[2] He was styled Lord St. John from 1576 to 1598. He was summoned to Parliament on 16 January 1581 in his father's barony as Lord St. John.[1] On 24 November 1598, he succeeded his father as 4th Marquess of Winchester. Paulet experienced great financial difficulties arising from his magnificent style of living and his lavish entertainment of Elizabeth I at Basing House.[1][3]
His wife, Lucy, was treated for cancer in 1614 by the court physician Théodore de Mayerne.[5] She died 1 October 1614 and was buried a month later in the Cecil vault in Westminster Abbey.[1]