Question: Which British peer and politician born in 1734 was a great-grandson of the 1st Duke of Marlborough?
Sentence (from "Earl Spencer (peerage)"): Earl Spencer is a title in the Peerage of Great Britain that was created on 1 November 1765, along with the title Viscount Althorp, of Althorp in the County of Northampton, for John Spencer, 1st Viscount Spencer.
Relevant evidence: No