He was the eldest son of John Throckmorton Esq. (1580-1614/15) by Agnes Wilford, and younger brother of prioress
Margaret Throckmorton. John's grandfather was
Sir Robert Throckmorton,
KG (1513-1581), of
Coughton Court, Warwickshire, and of
Weston Underwood, Buckinghamshire, who unlike his brothers during the
Reformation, one of whom, Job Throckmorton, became a
puritan, adhered to the Roman Catholic faith, which religion was persisted in by his descendants until the 20th century. ==Marriage==