James St Clair-Erskine, 2nd Earl of Rosslyn

General James St Clair-Erskine, 2nd Earl of Rosslyn GCB, PC (6 February 1762 – 18 January 1837), known as Sir James Erskine, Bt, between 1765 and 1789 and as Sir James St Clair-Erskine, Bt, between 1789 and 1805, was a Scottish soldier, politician, and Acting Grand Master of the Grand Lodge of Scotland, on behalf of King George IV.

Background and education
Erskine was the son of Lieutenant-General Sir Henry Erskine, 5th Baronet, and Janet, daughter of Peter Wedderburn (a Lord of Session under the judicial title of Lord Chesterhall) and sister of Alexander Wedderburn, 1st Earl of Rosslyn. Lord Rosslyn's earldom had been created with special remainder to his nephew, Erskine. Erskine succeeded as sixth baronet in 1765 at the age of three on the death of his father. He was educated at Edinburgh High School and Eton, and was commissioned in the 21st Light Dragoons in 1778.

Military career
Erskine was assistant Adjutant-General in Ireland in 1782. In 1793 became Adjutant-General, in which capacity he served at the Siege of Toulon and Corsica. In 1795 was promoted to colonel and appointed Aide-de-Camp to King George III. He became a major-general in 1798, lieutenant-general in 1805 and general in 1814. In 1806 he was a member of the special mission to Lisbon which resulted in Sir Arthur Wellesley (later Duke of Wellington) being sent to the peninsula. He also saw action in Denmark and the Netherlands.

Political career
Erskine was a member of the House of Commons for the English pocket boroughs of Castle Rising between 1782 and 1784 and Morpeth between 1784 and 1796. Initially a Whig, an adherent of Edmund Burke and an active supporter of Charles James Fox against William Pitt the Younger in the debates over the East India Company, he was one of the managers of the Impeachment of Warren Hastings. In 1789, on inheriting the Rosslyn and Dysart estates from his cousin James Paterson St Clair, he adopted the name St Clair before his own surname. In 1796 was elected for the Dysart Burghs in Fife, a constituency traditionally under the St Clair influence.

In January 1805, he succeeded his uncle as Earl of Rosslyn according to the special remainder, being by this time considered a Tory, and after the end of the Napoleonic Wars continued his political career in the House of Lords. He was a member of the cabinet as Lord Privy Seal from 1829 to 1830 under the Duke of Wellington's and Lord President of the Council under Sir Robert Peel from 1834 to 1835. In 1829 he was sworn of the Privy Council.

Family
Lord Rosslyn married Harriet Elizabeth, daughter of the Hon. Edward Bouverie, in 1790. She died in August 1810. Rosslyn remained a widower until his death in January 1837, aged 74. He was succeeded by his son, James.