John Conrad Russell, 4th Earl Russell (16 November 1921 – 16 December 1987) was the eldest son of the philosopher and mathematician Bertrand Russell (the 3rd Earl) and his second wife, Dora Black. His middle name was a tribute to the writer Joseph Conrad, whom his father had long admired. He was the great-grandson of the 19th century British Whig Prime Minister Lord John Russell. He succeeded to the earldom on the death of his father on 2 February 1970.