James St Clair-Erskine, 3rd Earl of Rosslyn

General James Alexander St Clair-Erskine, 3rd Earl of Rosslyn PC, DL (15 February 1802 – 16 June 1866), styled Lord Loughborough from 1805 to 1837, was a Scottish soldier and Tory politician. A General in the British Army, he also held political office as Master of the Buckhounds between 1841 and 1846 and again in 1852 and as Under-Secretary of State for War in 1859.

Background
Rosslyn was the son of James St Clair-Erskine, 2nd Earl of Rosslyn, by his wife Harriet Elizabeth Bouverie, daughter of the Honourable Edward Bouverie.

Military career
Rosslyn entered the British Army in 1819. He purchased a captaincy in the 9th Light Dragoons in 1823 and a lieutenant-colonelcy in 1828. He was promoted to Major-General in 1854, to Lieutenant-General in 1859 and to General in May 1866. In 1864 he was appointed a Colonel of the 7th Hussars. Lord Rosslyn also commanded the Auxiliary Cavalry Regiment, The Fife Mounted Rifle Volunteers from 1860 until his death in 1866.

Political career
Rosslyn was returned to Parliament for Dysart Burghs, in Fife, in 1830, a seat he held until 1831, and then represented Grimsby from 1831 to 1832. He succeeded his father in the earldom in 1837. In 1841 he was sworn of the Privy Council and appointed Master of the Buckhounds under Sir Robert Peel, which he remained until the government fell in 1846. He held the same office from February to December 1852 under Lord Derby, and was briefly Under-Secretary of State for War under Derby from March to June 1859.

Lord Rosslyn was also a Deputy Lieutenant for Fife.

Family
Lord Rosslyn married Frances Wemyss (16 September 1794 – 30 September 1858), daughter of Lieutenant-General William Wemyss, of Wemyss Castle, Fife, in 1826. They had two sons and one daughter. Lord Rosslyn died in June 1866, aged 64, and was succeeded in the earldom by his only surviving son, Robert.