Which British peer and politician born in 1734 was a great-grandson of the 1st Duke of Marlborough?
John Spencer, 1st Earl Spencer John Spencer, 1st Earl Spencer (19 December 1734 – 31 October 1783) was a British peer and politician.
Richard Longfield, 1st Viscount Longueville Richard Longfield, 1st Viscount Longueville (1734–1811) was an Irish Member of Parliament and later a peer.