(1622–83). Sidney was a famous Whig martyr and apologist. His brother, the 3rd earl of Leicester, was a strong supporter of the Commonwealth and Sidney fought for Parliament at Marston Moor
, where he was wounded. He refused to serve on the court that tried Charles I but joined the Council of State
in 1652. He disapproved of Cromwell's Protectorate but rejoined the Council of State in 1659. At the Restoration he was abroad on diplomatic missions and prudently decided to stay there. He returned to England
in 1677 just as the Popish plot
was about to explode. He joined Shaftesbury's Whig opposition and, though a theoretical republican, took money from Louis XIV to embarrass Charles II, leaving Macaulay
to lament that a ‘hero, philosopher and patriot’ should have fallen so low. In 1683 he was tried before Jeffreys
for involvement in the Rye House plot
and convicted on shaky evidence. A manuscript discourse on government, written in reply to Filmer in 1680, and not published until after Sidney's death, was produced to show that he advocated that the people were the source of all authority and had the right to bring tyrannical monarchs to justice. In his statement at the block, Sidney wrote that he died for ‘that Old Cause in which I was from my youth engaged’. Macaulay wrote that he died ‘with the fortitude of a stoic’ but Burnet
, while admitting Sidney's bravery and sincerity, observed that his ‘rough and boisterous temper could not bear contradiction’.
J. A. Cannon
Algernon Sidney, 1622–83, English politician; son of Robert Sidney, earl of Leicester. He served in the parliamentary forces during the English civil war and was a member (1652–53) of the council of state of the Commonwealth, but he opposed the dictatorial rule of Oliver Cromwell. Reappointed (1659) to the council of state, he was abroad at the time of the Restoration (1660) and remained there until 1677, when he returned to England to attend to personal affairs. He soon became associated with the opposition to Charles II, joining Lord William Russell and others in negotiations with French agents and in vague plots for an insurrection, perhaps to place the duke of Monmouth on the throne. His implication in these conspiracies was discovered by the exposure of the Rye House Plot. After a brutal and arbitrary trial by Judge Jeffreys, Sidney was convicted of treason and executed. Sidney's liberal ideals were set forth in his Discourses Concerning Government (1698), a treatise that had great influence on 18th-century political thought, especially in the American colonies.
See biography by A. C. Ewald (2 vol., 1873); J. Scott, Algernon Sidney and the English Republic 1623–1677 (1988).