[4] He was the son of the Conservative politician and diplomat Duff Cooper, later Viscount Norwich, and of Lady Diana Manners, a celebrated beauty and society figure.

[8] Because his father as Minister of Information was high on the Nazi enemies list of British politicians, Norwich's parents feared for their son's safety in the event of a German invasion of Britain.

In 1940 they decided to send him away after the US ambassador to Britain, Joseph P. Kennedy, offered to bring him to the United States with other evacuee children on board the SS Washington.

[13] His subsequent books included histories of Sicily under the Normans (1967, 1970), Venice (1977, 1981), the Byzantine Empire (1988, 1992, 1995), the Mediterranean (2006) and the Papacy (2011), amongst others (see list below).

He wrote and presented some 30 television documentaries, including The Fall of Constantinople, Napoleon's Hundred Days, Cortés and Montezuma, The Antiquities of Turkey, The Gates of Asia, Maximilian of Mexico, Toussaint l'Ouverture of Haiti, The Knights of Malta, Treasure Houses of Britain, and The Death of the Prince Imperial in the Zulu War.

[21][22] Christmas Crackers were compiled from whatever attracted Norwich: letters and diaries and gravestones and poems, boastful Who's Who entries, indexes from biographies, word games such as palindromes, holorhymes and mnemonics, occasionally in untranslated Greek, French, Latin, German or whatever language they were sourced from, as well as such oddities as a review from the American outdoors magazine Field and Stream concerning the republication of Lady Chatterley's Lover.

[28] Norwich lived for much of his life in a large detached Victorian house in Warwick Avenue, in the heart of Little Venice in Maida Vale, London, very close to Regent's Canal.

[3][13] Norwich was appointed to the Royal Victorian Order as a Commander in 1992 by Elizabeth II, as part of the celebrations to mark the 40th anniversary of her accession.