lord treasurer of England under King James I (ruled 1603–25). Although most historians regard him as James's most competent finance minister, he fell from power because his efforts at economy offended all factions in the government.

Cranfield spent his early career as a London merchant and financier. In 1612 he became acquainted with the lord privy seal, Henry Howard, earl of Northampton, and through Northampton's patronage, he was made surveyor general of the customs (1613).

After Northampton's death in 1614, Cranfield attached himself to the royal favourite, George Villiers, who eventually became the powerful duke of Buckingham. By 1620 Buckingham had found Cranfield a position on the privy council, where he quickly acquired a reputation as a financial reformer, though he was unsuccessful in his warnings to James I about the dangers of monopolies. Cranfield became lord treasurer in 1621 and a year later was created earl of Middlesex.

As minister in charge of finances, Middlesex was somewhat successful in increasing the King's revenues, but he soon alienated both James and Buckingham by his attempts to reduce royal expenditures. He opposed war with Spain on financial grounds, and, as a consequence, a prowar Parliament led by Buckingham and Prince Charles (later King Charles I) impeached him in 1624. Cranfield warned Buckingham of the dangers of such a precedent and told the Prince that he would one day “have his belly full of Parliaments.” Found guilty of maladministration and corruption, Middlesex was fined and temporarily imprisoned. He spent the rest of his life in retirement, receiving a full pardon from King Charles I in 1626.