His father was Sir Alexander MacFarquhar, a member of the Indian Civil Service and later a senior diplomat at the United Nations.

[2] After spending part of his national service from 1949 to 1950 in Egypt and Jordan as a second lieutenant in the Royal Tank Regiment, he went up to Keble College, Oxford to read Philosophy, Politics and Economics, obtaining a BA in 1953.

In 1969 he was a senior research fellow at Columbia University in New York City, and in 1971 he returned to England to hold a similar fellowship at the Royal Institute of International Affairs.

[3] In the 1966 general election, MacFarquhar fought the Ealing South constituency for the Labour Party but failed to dislodge the sitting Conservative MP.

Two years later, he was Labour candidate who attempted to retain the Meriden seat in a by-election; he was on the wrong end of an 18.4% swing at the height of the Wilson government's unpopularity.

[citation needed] Following the defeat of George Brown in 1970 and favourable boundary changes, MacFarquhar was selected to fight the Belper constituency, and at the February 1974 general election succeeded in winning the seat from its sitting Conservative MP Geoffrey Stewart-Smith.

He abstained on a vote to remove the disqualification of left-wing Labour councillors in Clay Cross who had broken council housing laws enacted by the previous Conservative government.

Volume three of his study The Origins of the Cultural Revolution: The Coming of the Cataclysm 1961-1966 (1997) won the Joseph Levenson Book Prize for 1999.