William Kerr, 2nd Marquess of Lothian
William Kerr, 2nd Marquis of Lothian, KT (1661–28 February 1722) was a Scottish peer and soldier.
Kerr was the eldest son of Robert Kerr, 1st Marquis of Lothian and his wife, Jane. On 30 June 1685, he married his cousin, Lady Jean Campbell (third daughter of Archibald Campbell, 9th Earl of Argyll) and they had five children:
- William Kerr, styled Earl of Ancram, later 3rd Marquis of Lothian (1690-1767)
- Lady Anne (d. 1727), married Alexander Home, 7th Earl of Home
- Lady Jean (d. 1768), married William Cranstoun, 5th Lord Cranstoun
- Lady Elizabeth (d. 1758), George Ross, 13th Lord Ross
- Lady Mary (d. 1768), married her cousin Alexander Hamilton.
Kerr was a Commissioner of Supply in 1685, 1686, 1702 and 1704. He succeeded to his cousin's title of Lord Jedburgh in 1692, was appointed Colonel of the 7th Regiment of Dragoons in 1696 and of the Scots Regiment of Foot Guards in 1707. He had been appointed a Brigadier General in 1720, a Major General in 1707, a Lieutenant General in 1707 and a Knight of the Thistle in 1705. He supported the Act of Union 1707 and was a Representative Peer in 1708 and from 1715 until his death.