William Kerr, 6th Marquess of Lothian,, was a British soldier, landowner and politician. He was the son of William Kerr, 5th Marquess of Lothian. He served as a representative peer from 1817 to 1824.

The Queen's Edinburgh Light Infantry Militia was an auxiliary regiment raised in and around the city of Edinburgh in Scotland. It was formed in 1798 and reformed in 1802, but had links with earlier Fencible and Volunteer units from the area. It served in home defence during the Napoleonic Wars and the Crimean War. Later it became a battalion of the Royal Scots and saw active service in South Africa during the Second Boer War. It served as a Special Reserve training unit in World War I, but after 1921 the militia had only a shadowy existence until its final abolition in 1953.