Sir Marcus Lowther-Crofton, 1st Baronet (died 17 January 1784) was an Anglo-Irish politician.
[1] He was born Marcus Lowther, the son of Gorges Lowther MP, of Kilrue, County Meath, and Jane Beresford, daughter of Sir Tristram Beresford, 3rd Baronet and Nichola Sophia Hamilton.
[1] On 9 September 1743 he married Catherine Crofton, daughter of Sir Edward Crofton, 3rd Baronet and Mary Nixon, and in 1745 he legally changed his surname to Lowther-Crofton.
[1] Lowther-Crofton, like his father and his brother Gorges Lowther, represented Ratoath in the Irish House of Commons between 1753 and 1760.
His daughter Sophia married the High Court judge Peter Metge; another daughter Catherine married Sir James Quaile Somerville, 3rd Baronet of Somerville, and was the grandmother of the first Baron Athlumney.