Robert Monsey Rolfe, 1st Baron Cranworth, PC (18 December 1790 – 26 July 1868) was a British lawyer and Liberal politician.

[note 1] Rolfe, a relative of Admiral Lord Horatio Nelson,[2] was educated at Bury St Edmunds, Winchester, Trinity College, Cambridge,[3] Downing College, Cambridge (of which he was elected fellow) [4] and was called to the bar, Lincoln's Inn, in 1816.

[5] Cranworth represented Penryn and Falmouth in Parliament from 1832 until he was appointed a Baron of the Exchequer in 1839.

[6] Cranworth continued to hold the chancellorship also in the administration of Lord Palmerston until the latter's resignation in 1858.

Lord Cranworth died at his seat, Holwood House, on 26 July 1868, aged 77, after a short illness related to the heat.