James, Earl of Lonsdale (b. 1736) succeeded his cousin Viscount Lonsdale in the Baronetcy and was created on 24 May 1784 Baron Lowther of Lowther, Bardon Kendal, Baron Burgh, Viscount Londsdale, Viscount Lowther and Earl of Lonsdale. In 1761 he married Mary, daughter of John, Earl Bute. They had no issue and so in 1797 he obtained a new patent creating him Baron and Viscount Lowther with remainder to the male heirs of his cousin, Rev. Sir William Lowther, Bt.
For another miniature of a member of the Londale family, Lady Lonsdale, see lot 373.