In 1950, he was appointed Private Secretary to Princess Elizabeth, who was then Duchess of Edinburgh and heir presumptive to the British throne. From her accession in 1952 until 1972, he served as her Assistant Private Secretary under Sir Michael Adeane. On Adeane's retirement in 1972, he was promoted to Private Secretary. He held this post until his retirement in 1977 and returned to Eton as its Provost. He was granted the honour of being a Permanent Lord in Waiting.[7]
Coat of arms of Martin Charteris, Baron Charteris of Amisfield
Crest
A dexter hand issuant paleways holding between the thumb and forefinger in bend sinister a pair of sculptor's callipers all Proper.
Escutcheon
Quarterly: 1st and 4th Argent a fess Azure within a double tressure flory counterflory Gules (Charteris); 2nd and 3rd Or a lion rampant Gules armed and langued Azure (Wemyss); over all at the fess point a crescent Sable for difference.
Supporters
Dexter a scribe soberly attired holding in his exterior hand a quill pen Proper, sinister an Officer of the King's Royal Rifle Corps in the uniform worn circa 1904 Proper.
In the first two seasons of the Netflix series The Crown, Charteris was portrayed by Harry Hadden-Paton. In seasons 3 and 4, the more mature Charteris was played by Charles Edwards. Charteris retired in 1977 as Private Secretary. In The Crown he was portrayed as holding the office much longer than in reality.