James Johnston Clark (1809 – June 1891) was a Unionist politician in Ireland.
He inherited Largantogher House, Maghera, County Londonderry on the death of his father in 1842 and was appointed High Sheriff of County Londonderry for 1849.
[1] He served as a Unionist Member of Parliament for County Londonderry from 9 March 1857 until 1859.
Clark's grandson was James Lenox-Conyngham Chichester-Clark and his great-grandson was Prime Minister of Northern Ireland, Lord Moyola.
This article about a Member of the Parliament of the United Kingdom, for a constituency in Ireland between 1801 and 1922 is a stub.