Sir Herbert Stanley Marchant KCMG OBE (18 May 1906 – 8 August 1990) was a schoolmaster, at Bletchley Park the codebreaking centre in World War II, and then a diplomat.
He was ambassador to Cuba (1960–63) and Tunisia (1963–66); remembered for replying to British newspapers during the Cuban Missile Crisis that “Everything is perfectly quiet here” (in Cuba).
He was an assistant master at Harrow School 1928–39, teaching French and German, and later Russian.
The head Eric Jones had taken over sole responsibility from 1942, after personal rivalries between the original staff of Hut 3.
Then he became Assistant Director of the Institute of Race Relations 1966–68, and United Kingdom representative on the United Nations Committee for the Elimination of Racial Discrimination 1969–73.