He was born in the parish of St Laurence Jewry, London. His great-grandfather, Richard Rich, was a wealthy mercer and sheriff of the city of London in 1441. Rich's father was probably also a mercer, but he sent his son to the Middle Temple, where Sir Thomas More was among his acquaintances. More told him at the time of his trial that he was reputed light of his tongue, a great dicer and gamester, and not of any commendable fame; but he was a commissioner of the peace in Hertfordshire in 1528, and in the next autumn became reader at the Middle Temple.
Other preferments followed, and in 1533 he was knighted and became solicitor-general, in which capacity he was to act under Thomas Cromwell as a "lesser hammer" for the demolition of the monasteries, and to secure the operation of Henry VIII's act of supremacy. He had an odious share in the trials of More and Bishop Fisher. In both cases his evidence against the prisoner included admissions made in friendly conversation, and in More's case the words were given a misconstruction that could hardly be other than wilful. More expressed his opinion of the witness in open court with a candour that might well have dismayed Rich.
Rich became the first chancellor (April 19, 1536) of the Court of Augmentations established for the disposal of the monastic revenues. His own share of the spoil, acquired either by grant or purchase, included Leez (Leighs) Priory and about a hundred manors in Essex. He was Speaker of the House of Commons in the same year, and advocated the king's policy. In spite of the share he had taken in the suppression of the monasteries, and of the part he was to play under Edward VI, his religious convictions remained Roman Catholic. His testimony helped the conviction of Thomas Cromwell, and he was a willing agent in the Catholic reaction which followed. Anne Askew stated that the Chancellor Wriothesley and Rich screwed the rack at her torture with their own hands.
Rich was an executor of the will of Henry VIII, on which much suspicion has been thrown, and on February 26, 1548 he became Baron Rich of Leez. In the next month he succeeded Wriothesley as chancellor, an office in which he found full scope for the business and legal ability he undoubtedly possessed. He supported Protector Somerset in his subversive reforms in church matters, in the prosecution of his brother Thomas Seymour, and in the rest of his policy until the crisis of his fortunes in October 1549, when he deserted to Warwick (afterwards Northumberland), and presided over the trial of his former chief. His daughter had married Warwick's son, and both men were at heart no friends to the reformed religion.
Nevertheless, Rich took part in the prosecution of bishops Stephen Gardiner and Edmund Bonner, and in the harsh treatment accorded to the future Mary I of England. Mary on her accession showed no ill-will to Rich. He retired from the chancellorship on the grounds of ill-health in the close of 1551, at the time of the final breach between Northumberland and Somerset. He was now sixty years old, and there is no reason to suspect the sincerity of his plea. There is an improbable story, however, to the effect that Rich warned Somerset of his danger in the Tower of London, and that the letter was delivered by mistake to Thomas Howard, 3rd Duke of Norfolk, who handed it to Northumberland.
Lord Rich took an active part in the restoration of the old religion in Essex under the new reign, and was one of the most active of persecutors. His reappearances in the privy council were rare during Mary's reign; but under Elizabeth he served on a commission to inquire into the grants of land made under Mary, and in 1566 was sent for to advise on the question of the queen's marriage. He died at Rochford, Essex, on the 12th of June 1567, and was buried in Felsted church.
In Mary's reign he had founded a chaplaincy with provision for the singing of masses and dirges, and the ringing of bells in Felsted church. To, this was added a Lenten allowance of herrings to the inhabitants of three parishes. These donations were transferred in 1564 to the foundation of a grammar school at Felsted for instruction, primarily for children born on the founder's manors, in Latin, Greek and divinity. The patronage of the school remained in the family of the founder until 1851. By his wife Elizabeth Jenks, or Gynkes, he had fifteen children. The eldest son Robert (1537?-1581), second Baron Rich, supported the Reformation, and his grandson Robert, third lord, was created earl of Warwick in 1618.
The chief authorities are the official records of the period covered by his official life, calendared in the Rolls Series. See also AF Pollard, England under Protector Somerset (1900); P Morant, History of Essex (2 vols., 1768); RW Dixon, History of the Church of England (6 vols., 1878-1902); and lives in J Sargeaunt's History of Felsted School (1889), Lord Campbell's Lives of the Lord Chancellors (1845-69), and CH & T Cooper's Athenae Cantabrigienses (2 vols., 1858-61).