Chidiock's father Peter appears to have been the youngest son of Henry Tichborne (born circa 1474) and Anne Mervin (or Marvin) but the records are unclear. Peter was clerk of the Crowne at the trial of Sir Nicholas Throckmorton in 1554 and was an ardent Catholic supporter. Being the youngest son of a youngest son he was of little means and required to make his own way. He secured an education and the patronage of his distant kinsman, Lord Chidiock Paulet (1521–1574, son of the 1st Marquess of Winchester), after whom he named his son. In later life he spent many years imprisoned unable to pay recusancy fines. Chidiock's mother was Elizabeth Middleton, daughter of William Middleton (grandson of Sir Thomas Middleton of Belso, Kt.) and Elizabeth Potter (daughter of John Potter of Westram). William had been servant to John Islip, Abbot of Westminster, and a banner bearer at Islip's funeral 1532, and later bought lands in Kent.