Sir John Willoughby (about 1421–1477), of Brook, was an English landowner, administrator, soldier and politician who was elected as MP for Wiltshire, where he lived, and for the adjoining seat of Somerset.
[2] By 1445 he had acquired Brook Hall at Westbury in Wiltshire through marriage to the heiress, and had made it his principal home, but retained lands in Lincolnshire where in that year he was appointed to a royal commission.
As England sank into civil war, he supported the ruling Lancastrian party, being appointed in December 1459 to a commission of array raising troops and in March 1461 fighting on the losing side for King Henry VI at the Battle of Towton.
He sat again as MP for Wiltshire in 1467, being appointed to all royal commissions for the county, and served another term as its sheriff in 1472.
[citation needed] The other co-heiress, her sister Elizabeth Cheyne, married the MP Sir John Colshull.