Algernon Sidney

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Algernon Sidney

Death: Died
Cause of death: Executed for treason
Immediate Family:

Son of Robert Sidney, 2nd Earl of Leicester and Dorothy Sidney, Countess of Leicester
Brother of Lady Dorothy Spencer; Philip Sidney, 3rd Earl of Leicester; Lucy Sydney; Henry Sidney, 1st Earl of Romney and Robert Sidney

Managed by: Carole (Erickson) Pomeroy, Vol. ...
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About Algernon Sidney

Algernon Sidney or Sydney (14 or 15 January 1623 – 7 December 1683) was an English politician, republican political theorist, colonel, and opponent of King Charles II of England, who became involved in a plot against the King and was executed for treason.

Early life

Sidney's father was Robert Sidney, 2nd Earl of Leicester, a direct descendant of John Dudley, 1st Duke of Northumberland and the great-nephew of Sir Philip Sidney. Sidney's mother was Dorothy Percy, daughter of Henry Percy, 9th Earl of Northumberland. Sidney was born at Baynard's Castle, London, and was raised at Penshurst Place in Kent. Sidney's mother wrote to her husband in November 1636 that she had heard her son "much comended by all that comes from you...[for] a huge deall of witt and much sweetness of nature". After spending time in Ireland after his father was appointed Lord Lieutenant of that country, Sidney returned to England in 1643.

English Civil War and Republic

Despite having earlier vowed that only "extreame necessity shall make me thinke of bearing arms in England", he served in the New Model Army. He fought at the Battle of Marston Moor in 1644, where an observer wrote: "Colonel Sidney charged with much gallantry in the head of my Lord Manchester's regiment of horses, and came off with many wounds, the true badges of his honour". In 1645 he was elected to the Long Parliament as Member of Parliament for Cardiff where he opposed compromising with the King, Charles I, and in 1648 opposed the purge of moderates which formed the Rump Parliament. Despite being a commissioner for the trial of Charles, Sidney also opposed the decision to have him executed due to the questionable lawfulness and wisdom of the decision. This led to the famous exchange:

First, the King could be tried by noe court; secondly, that noe man could be tried by that court. This being alleged in vaine, and Cromwell using these formall words (I tell you, wee will cut off his head with the crowne upon it) I...immediately went out of the room, and never returned.

However by 1659 Sidney had changed his opinion, declaring the king's execution as "the justest and bravest act...that ever was done in England, or anywhere".

In 1653 when Cromwell's army entered Parliament to dissolve it after a Bill was introduced that would have made elections freer, Sidney refused to leave the House until threatened with physical removal. He regarded Cromwell as a tyrant. In retirement, Sidney was bold enough to outrage the Lord Protector by allegedly putting on a performance of Julius Caesar, with himself in the role of Brutus. He was for a time the lover of Lucy Walter, later the mistress of Charles, Prince of Wales.

However Sidney regarded the Republic as vigorously pursuing England's national interests (in contrast to the Stuart's record of military failure), writing in his Discourses Concerning Government:

...such was the power and wisdom and integrity in those that sat at the helm, and their diligence in chusing men only for their merit was blessed with such success, that in two years our fleets grew to be as famous as our land armies; the reputation and power of our nation rose to a greater height, than when we possessed the better half of France, and the kings of France and Scotland were our prisoners. All the states, kings and potentates of Europe, most respectfully, not to say submissively, sought our friendship; and Rome was more afraid of Blake and his fleet, than they had been of the great king of Sweden, when he was ready to invade Italy with a hundred thousand men.

Baltic Ambassador

After Cromwell's death in 1658, the army abolished the Protectorate in 1659 and reconvened the Rump Parliament, with Sidney taking up his seat in the Commons. During 1659-1660 he was part of a delegation to help arbitrate peace between Denmark and Sweden, as war would threaten England's naval supplies, as well as those of the Dutch. The delegation was commanded by Edward Montague, with Sidney and Sir Robert Honeywood. The third planned plenipotentiary, Bulstrode Whitelocke, declined because: "I knew well the overruling temper and height of Colonel Sydney". Sidney discarded conventional diplomatic norms ("a few shots of our cannon would have made this peace") in order to impose a peace favourable to England. Due to the Swedish king Charles X being unable to immediately receive them, the delegation negotiated with the Dutch on forming a joint fleet to impose peace terms. Charles X complained that the English "wish to command all, as if they were masters". Sidney in person handed Charles with the treaty proposal (already accepted by Denmark), threatening military action. Sidney recorded that Charles "in great choler...told us, that we made projects upon our fleets, and he, laying his hand upon his sword, had a project by his side". Sidney would not back down and an observer wrote: "Everyone is amazed how Sidney stood up to him". However Montague planned to go back to England with the fleet, leading Sidney to give "his opinion, [that] for sending away the whole fleet he thought he should deserve to lose his head". Despite this curtailment England's influence, a treaty was signed on 27 May 1660 by Denmark, Sweden, France, England and Holland. It was during this period that Sidney signed the visitor's book at the University of Copenhagen with: "PHILIPPUS SIDNEY MANUS HAEC INIMICA TYRANNIS EINSE PETIT PLACIDAM CUM LIBERTATE QUIETEM" ("This hand, enemy to tyrants, by the sword seeks peace with liberty").


Sidney was abroad when the monarchy was restored in 1660. His first reaction to the Restoration of the Stuart monarchy was to write:

Since the Parliament hath acknowledged a king, I knowe...I owe him duty and the service that belongs unto a subject, and will pay it. If things are carried in a legall and moderate way, I had rather be in employment, than without any.

However in light of his defence of the execution of Charles I, which was now unpopular in England, Sidney thought it wise to remain in exile in Rome: whilst he was prepared to submit he would not, he wrote, countenance "acknowledgement of our faults, in having bin against this king, or his father...I shall be better contented with my fortune, when I see theare was noe way of avoiding it, that is not worse than ruine". Here he was saved by a stranger from an assassination attempt. In 1663 during a trip to the Calvinist academy at the University of Geneva, Sidney wrote in the visitor's book: "SIT SANGUINIS ULTOR JUSTORUM" ("Let there be revenge for the blood of the just"). In Augsburg in April 1665 he was the target of another assassination attempt. When in Holland, Gilbert Burnet records, Sidney and other republicans:

...came to De Witt, and pressed him to think of an invasion of England and Scotland, and gave him great assurances of a strong party: and they were bringing many officers to Holland to join in the undertaking. They dealt also with some in Amsterdam, who were particularly sharpened against the king, and were for turning England again into a commonwealth. The matter was for some time in agitation at the Hague: but De Witt was against it, and got it to be laid aside. He said, their going into such a design would provoke France to turn against them: it might engage them in a long war, the consequences of which could not be forseen: and, as there was no reason to think that, while the parliament was so firm to the king, any discontents could be carried so far as to a general rising, which these men undertook for, so, he said, what would the effect be of turning England into a commonwealth, if it could possibly be brought about, but the ruin of Holland? It would naturally draw many of the Dutch to leave their country, that could not be kept and maintained but at a vast charge, and to exchange that with the plenty and security that England afforded. Therefore all that he would engage in was, to weaken the trade of England, and to destroy her fleet; in which he succeeded the following year beyond all expectation.

In mid-1666, Sidney was in Paris, where he negotiated with the king, Louis XIV. Louis subsequently wrote that Sidney "promised me to produce a great uprising...but the proposition he put to me to advance him 100,000 ecus...was more than I wished to expose on the word of a fugitive [so] I offered him [initially] only 20,000". He remained in France until 1677, when he returned to England.

Court Maxims

During 1665-66 Sidney wrote Court Maxims, in which he argued for a reversal of the Restoration of the monarchy: " death is the greatest evil that can befall a person, monarchy is the worst evil that can befall a nation". Sidney also claimed that an English republic would have a natural "unity of interest" with the Dutch Republic in "extirpat[ing] the two detested families of Stuart and Orange". Court Maxims was not published until 1996.

Restoration Crisis: 1677–1683

Sidney arrived in England in early September 1677. Upon his father's death Sidney inherited £5000 but had to gain the remaining £5000 through chancery courts, staying at Leicester House in London. Here he became involved in politics, with the French Ambassador Barillon writing on 6 October:

At the moment my most intimate liaison is with Mr. Algernon Sidney; he is the man in England who seems to me to have the greatest understanding of affairs; he has great relations with the rest of the Republican party; And nobody in my opinion is more capable of rendering service than him.

Due to his helping the fall of Lord Danby in December 1678, Sidney received 500 guineas from the French, getting another 500 guineas the next year. Sidney wished for an alliance of English and Dutch republicans against the Stuart-Orange alliance and told Barillon "that it is an old error to believe that it is against the interest of France to suffer England to become a republic". Sidney believed that it was a "fundamental principle that the House of Stuart and that of Orange are inseparably united".

After the dissolution of Charles II's last Parliament in 1681, Sidney, according to Burnet, helped write the answer to the king's declaration, entitled A Just and Modest Vindication of the Proceedings of the Two Last Parliaments: "An answer was writ to the king's declaration with great spirit and true judgment. It was at first penned by Sidney. But a new draught was made by Somers, and corrected by Jones".[8]

Sidney united with Lord Shaftesbury and others in plotting against the perceived royal tyranny, of a 'force without authority.' Sidney was later to be implicated in the Rye House Plot, a scheme to assassinate Charles and his brother.

[Trial and execution

On 25 June 1683 Sidney's arrest warrant was issued. During his arrest his papers were confiscated, including the draft of the Discourses. Lord Howard was the only witness but the law stated that two witnesses were necessary so the government used the Discourses as its second witness. Lord Chief Justice Jeffreys ruled: "Scribere est agere" ("to write is to act").

"An argument for the people", said the Solicitor General of the Discourses, "to rise up in arms against the King". In response, Sidney said that it was easy to condemn him by quoting his words out of context: "If you take the scripture to pieces you will make all the penmen of the scripture blasphemous; you may accuse David of saying there is no God and of the Apostles that they were drunk." Sidney was found guilty of treason and sentenced to death on 26 November. In The Apology of Algernon Sydney, in the Day of his Death, Sidney declared his life's work to:

...uphold the Common rights of mankind, the lawes of this land, and the true Protestant religion, against corrupt principles, arbitrary power and Popery...I doe now willingly lay down my life for the same; and having a sure witness within me, that God doth...uphold very littell sollicitous, though man doth condemne me.

Neither denying nor affirming the charge of treason for which he had been condemned, Sidney emphasized his principles while declaring on the scaffold: "We live in an age that makes truth pass for treason."

He was beheaded on 7 December 1683 and his remains buried at Penshurst.

Discourses Concerning Government

For Sidney absolute monarchy, in the form practiced by Louis XIV, was a great political evil. His Discourses Concerning Government (the text for which Sidney lost his life) was written during the Exclusion Crisis, as a response to Robert Filmer's Patriarcha, a defence of divine right monarchy, first published in 1680. Sidney was quite opposed to the principles espoused by Filmer and believed that the Sovereign's subjects had the right and duty to share in the government of the Realm by giving advice and counsel. It was Filmer's business, he wrote, "to overthrow liberty and truth." Patriarchial government was not 'God's will', as Filmer and others contended, because the "Civil powers are purely human ordinances."

In countering the Hobbesian argument that the coercive power of the monarchy was necessary to prevent the return of the Civil Wars, Sidney invoked Tacitus, the Roman historian, saying that the pax Romana, the Imperial peace, was the 'peace of death.' Rebellion may have dangerous consequences but

“ They who are already fallen into all that is odious, and shameful and miserable, cannot justify fear... Let the dangers never be so great, there is the possibility of safety while men have life, hands, arms and courage to use them but that people must surely perish who tamely suffer themselves to be oppressed. ”


After his death, Sidney was revered as the "whig patriot–hero and martyr". Burnet said of Sidney:

...a man of the most extraordinary courage, a steady man, even to obstinacy, sincere, but of a rough and boisterous temper, that could not bear contradiction, but would give foul language upon it. He seemed to be a Christian, but in a particular form of his own. He thought it was to be like a divine philosophy in the mind, but he was against all public worship, and every thing that looked like church. He was stiff to all republican principles, and such an enemy to every thing that looked like monarchy, that he set himself in a high opposition against Cromwell when he was made protector. He had indeed studied the history of government in all its branches beyond any man I ever knew.

In his study of political theory in Britain from 1689 to 1720, J. P. Kenyon said that Sidney's Discourses "were certainly much more influential than Locke's Two Treatises". Sidney's reputation suffered a blow when Sir John Dalrymple published his Memoirs of Great Britain and Ireland in 1771, which exposed him as a pensioner of Louis XIV. However, Sidney's influence on political thought in eighteenth-century Britain and Colonial America was probably second only to that of John Locke among seventeenth-century political theorists.

Thomas Jefferson believed Sidney and Locke to be the two primary sources for the American conception of liberty. John Adams wrote to Jefferson in 1823 on the subject of Sidney:

I have lately undertaken to read Algernon Sidney on government. ... As often as I have read it, and fumbled it over, it now excites fresh admiration [i.e., wonder] that this work has excited so little interest in the literary world. As splendid an edition of it as the art of printing can produce—as well for the intrinsic merit of the work, as for the proof it brings of the bitter sufferings of the advocates of liberty from that time to this, and to show the slow progress of moral, philosophical, and political illumination in the world—ought to be now published in America.

The libertarian philosopher Friedrich Hayek quoted Sidney's Discourses on the title page of his The Constitution of Liberty: "Our inquiry is not after that which is perfect, well knowing that no such thing is found among men; but we seek that human Constitution which is attended with the least, or the most pardonable inconveniences".

Algernon Sidney is one of the namesakes for Hampden-Sydney College in Virginia. The College formerly used the original spelling of Sydney. He was chosen because of the role his ideas played in molding the beliefs of the American Revolutionary thinkers.

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Algernon Sidney's Timeline

Age 60