Robert Monteith (1812 – 31 March 1884), DL, JP, was a Scottish politician and philanthropist, Deputy Lieutenant for the County of Lanark.
Robert Monteith was born in Glasgow, the only son of Henry Monteith (d. 1848), MP for Lanark Burghs. He was educated at Glasgow University and Trinity College, Cambridge, where he was a member of the Cambridge Apostles. He converted to the Roman Catholic Church in 1846 and was a prominent Christian socialist.
He married Wilhelmina Anne Mellish daughter of Joseph Mellish of Blythe, Nottinghamshire. They lived at Carstairs House.
Their son was:
Their daughter was:
He died at Carstairs House on 31 March 1884.
He was appointed Deputy Lieutenant for the County of Lanarkshire on 27 October 1855.
On 9 February 1870 he accompanied David Urquhart to a private audience with Pope Pius IX.