Sir Donald Gainer GBE KCMG (18 October 1891 – 30 July 1966) was a British diplomat who was successively Ambassador to Venezuela, Brazil and Poland.
He joined the British Consular Service in 1915 and was vice-consul successively in several towns in Norway (Narvik, Vardø, Christianssand, Tromsø, Bergen), then in Havana where he was chargé d'affaires between ambassadors.
[5] He left Brazil in 1947 to a complimentary column from The Times correspondent in Rio de Janeiro[6] and transferred to be ambassador to Poland.
Sir D.St.Clair Gainer is finely drawn by Patrick-Leigh Fermor as the British consul in Munich who bailed him out with a new passport - to replace the one which was stolen - and a five-pound note, returned a year later by Leigh-Fermor from Constantinople.
[10] He was knighted KCMG in 1944 on his appointment to Brazil[11] and given the additional, senior knighthood of GBE in the New Year Honours of 1950.