John Thurloe (June 1616 – 21 February 1668) was an English politician who served as secretary to the council of state in Protectorate England and spymaster for Oliver Cromwell and held the position of Postmaster General between 1655 and 1660. He was from Great Milton in Oxfordshire and of Lincoln's Inn, Origins Thurloe was born in Essex in 1616 and was baptised on 12 June. His father was Rev. Thomas Thurloe, Rector of Abbess Roding. Career He trained as a lawyer in Lincoln's Inn. He was first in the service of Oliver St John, solicitor–general to King Charles I and Lord Chief Justice of the Common Pleas. In January 1645, became a secretary to the parliamentary commissioners at the Treaty of Uxbridge. In 1647 Thurloe was admitted to Lincoln's Inn as a member. He remained on the sidelines during the English Civil War but after the accession of Oliver Cromwell, became part of his government. In March 1651, Thurloe accompanied Oliver St John as his secretary on his embassy to the United Provinces to propose a union between the Commonwealth and the Dutch. In 1652 he was named a secretary for state. In 1653 he became head of intelligence and developed a widespread network of spies in England and on the continent. These included the Dutch diplomat and historian Lieuwe van Aitzema, the mathematician John Wallis, who established a code-breaking department, as well as diplomat and mathematician Samuel Morland, who served as Thurloe's assistant. Thurloe's service broke the Sealed Knot, a secret society of Royalists and uncovered various other plots against the Protectorate. In 1654 he was elected to Parliament as the member for Ely. He supported the idea that Cromwell should adopt a royal title. In 1655 Thurloe became Postmaster General, a post he held until he was accused of treason and arrested in May 1660. His spies were able to intercept mail, and he exposed Edward Sexby's 1657 plot to assassinate Cromwell and captured would-be assassin Miles Sindercombe and his group. (Ironically, Thurloe's own department was also infiltrated: in 1659 Morland became a Royalist agent and alleged that Thurloe, Richard Cromwell and Sir Richard Willis – a Sealed Knot member turned Cromwell agent – were plotting to kill the future King Charles II.) About forty years after his death, a false ceiling was found in his rooms at Lincolns Inn; the space was full of letters seized during