Secretary (1779), then chairman (c. 1780) of the Yorkshire Association, which sought to shorten parliamentary terms and reform representation. Blamed the continuance of the Revolutionary War on legislators’ self- interested electioneering. Published six volumes of his correspondence and numerous pamphlets on religious toleration and parliamentary reform.
Son of Edward and Christian Catherine (Clifton) Wyvill of Edinburgh. Educated at Cambridge (LL.D. 1764). Married (1) his cousin Elizabeth Wyvill (1773). Married (2) Sarah Codling; several children.