John Underhill was born at Ettington, Warwickshire, in 1574. He was the son of Thomas Underhill (1516-1571) and Ann Wood, and grandson of Thomas Underhill (1485-1520) and Anne Wynter (1485-1545). In 1617 he served as a gentleman usher for Sir Francis Bacon at York House, which was the resident of the Keeper of the Seals while King James was on his Northern tour.
John Underhill would go on to marry Alice, Viscountess Saint Alban (1592-1650), the recent widow of Sir Francis Bacon (1561-1626). They married on April 10, 1626 at Saint Martin-in-the-Fields, a scarce eleven days after Sir Francis’ death. This is the same church where Francis Bacon had been baptized sixty-five years previously. The two are reputed to have maintained a relationship for some time prior to their marriage. Underhill was knighted for unknown services only two months later. The Viscountess separated from Underhill a few short years later, in 1639, and lived the rest of her life mainly with her mother who had been married four times herself. She died on June 29, 1650. Sir John Underhill was laid to rest on April 14, 1679, at Saint Giles-in-the-Fields in London.