[3] At Eton he was a contemporary of Prince Alexander of Teck, later Governor-General of South Africa and of Canada, Geoffrey Dawson, later editor of The Times, and the author Maurice Baring.
In early 1901 was appointed an acting Third Secretary[4] to accompany a special diplomatic mission to announce King Edward's accession, to the governments of Denmark, Sweden and Norway, Russia, Germany, and Saxony.
[5] He went to Addis Ababa in 1903 as Assistant in HM Agency, where he became Acting Agent and Consul-General from 1903 to 1904 and Chargé d'Affaires at the British Legation in Abyssinia, 1906–07.
[3] While in Abyssinia, Clerk worked to curb the excesses of the slave trade in the border regions of Sudan and Uganda and gained the nickname of 'the Buffalo'.
[7] In the aftermath of the First World War, Clerk was very sympathetic to the cause of the national minorities of the former Austria-Hungary and to the liberal ideals associated with the journal The New Europe.
There were mixed views on Clerk's appointment to Paris in the troubled days of 1934, following the sudden retirement of his predecessor Lord Tyrrell on the grounds of ill health.