Chequers Antiques has dated this piece to the Georgian era.

The sitter is, according to the inscription on the back, Lt Col Robert Swinton, son of John, Lord Swinton, (1723-1799) a Scottish advocate who became Senator of the College of Justice, born 1773 and who served in the Honourable East India Company Service. He married but had no issue, and died in 1821. He is buried at St John’s church, Princes Street, Edinburgh.
The taping at the back has been redone and the inscription, in ballpoint, has also been redone, presumably replacing an older label. There is a ring affixed to the top for hanging it.
Chequers Antiques has dated this piece to the Georgian era.
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