Sir William Waller (c.1639 – 18 July 1699) was an English justice and politician from Middlesex. He was active against Roman Catholics during the alleged Popish Plot 1678-1679 and was removed from the commission of the peace in April 1680 for his overzealousness. He sat in the House of Commons between 1680 and 1682 when he fled to Holland although he retained the seat until 1685. He returned to England with Prince of Orange in November 1688.[1]