John Singleton Copley, 1st Baron Lyndhurst (1772-1863), Lord Chancellor of England, was a British politician. was born at Boston, Massachusetts, in 1772. The son of painter John Singleton Copley, he was educated at a private school and Cambridge University. Called to the bar at Lincolns Inn in 1804, he gained a considerable practice. In 1817 he was one of the counsel for Dr J. Watson, tried for his share in the Spa Fields riot. Copley's performance attracted the attention of Castlereagh and other Tory leaders, and he entered parliament as member for Yarmouth in the Isle of Wight. He afterwards sat for Ashburton, 1818-1826, and for Cambridge University 1826-1827.

In 1819, the year he became Solicitor-General, he married the widow of Lieut.-Col. Charles Thomas of the Coldstream Guards. He became Attorney-General in 1824, Master of the Rolls in 1826 and Lord Chancellor in 1827, with the title of Lord Lyndhurst.

As solicitor-general he took a prominent part in the trial of Queen Caroline and was opposed to the Liberal measures which marked the end of the reign of George IV and the beginning of that of William IV. He was lord chief baron of the exchequer from 1831 to 1834. During the Melbourne administration from 1835 to 1841 he figured conspicuously as an obstructionist in the House of Lords. His former adversary Lord Brougham, disgusted at his treatment by the Whig leaders, soon became his most powerful ally in opposition. Lyndhurst held the chancellorship from (1827-1830, 1834-1835, and 1841-1846. He was In regard to Catholic emancipation, so in the agitation against the corn laws, he opposed reform until Peel, his chief, gave the signal for concession.

After 1846 and the disintegration of the Tory party over Peel's adoption of free trade, Lord Lyndhurst did not attend parliament sessions as often, but he continued to take a lively interest in public affairs and to make speeches. His address to the House of Lords on 19th June 1854, on the war with Russia, made a sensation in Europe, and throughout the Crimean War he was a strong advocate of the energetic prosecution of hostilities. In 1859 he denounced the restless ambition of Napoleon III. His last speech was delivered in the House of Lords at the age of eighty-nine. He died in London on 12 October 1863. He left no male issue, and the title became extinct.

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The Lord Brougham and Vaux | width="40%" style="text-align: center;" |Lord Chancellor
1834–1835 | width="30%" |Succeeded by:
In Commission

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The Lord Cottenham | width="40%" style="text-align: center;" |Lord Chancellor
1841–1846 | width="30%" |Succeeded by:
The Lord Cottenham