Arthur Capel, 1st earl of Essex (born 1631/32—died July 13, 1683, London) was an English statesman, a member of the “Triumvirate” that dominated policy at the time of the Popish Plot (1678).
The son of Arthur Capel, 1st Baron Capel, who was executed by the Parliamentarians in 1649, he was, after the Restoration of Charles II, created Viscount Malden and earl of Essex (April 1661). Although his antagonism to court life, to Roman Catholicism, and to extension of the royal prerogative alienated Charles II, he was nevertheless appointed to a succession of offices. As lord lieutenant of Ireland (1672–77), Essex purged the country’s financial administration, repelled attempts to exploit the Irish land market, and generally endeavoured to improve the condition of Roman Catholics. As a lord of the treasury (March–November 1679), he worked with the earls of Halifax and Sunderland, at first supporting Halifax’ scheme to impose statutory limitations should the Roman Catholic duke of York (afterward James II) become king.
His political attitude became more and more intolerant of the Roman Catholic flavour of the court, and, as member of the Privy Council, he joined Anthony Ashley Cooper, 1st earl of Shaftesbury, in voting (November 1680) for the exclusion of James from the succession. A fervent Protestant, he may have taken part in the Rye House Plot (June 1683) to assassinate the allegedly pro-Catholic Charles II and his brother James, and he was certainly among the supporters of Charles’s illegitimate Protestant son, James Scott, Duke of Monmouth. He was arrested and imprisoned in the Tower of London, where he was found with his throat cut. The violence with which the wound had been inflicted made it uncertain whether or not his death was a suicide. If suicide, his motive may have been to prevent an attainder and preserve his titles and estates for his family. He had one surviving son, Algernon (1670–1710), 2nd Earl of Essex.