Lascelles returned to
Britain and was appointed Assistant Private Secretary to
Edward, Prince of Wales in 1920, serving in that role until resigning in 1929, citing differences with the prince. From 1931 to 1935, he was
Secretary to the Governor General of Canada,
Vere Ponsonby, 9th Earl of Bessborough. Lascelles became the Assistant Private Secretary to
George V in the latter months of 1935. When the Prince of Wales ascended the throne as Edward VIII on the death of George V in January 1936, Lascelles served briefly as the new King's Assistant Private Secretary, although he never saw the King during this phase. He soldiered on through Edward's short reign and the protracted crisis of the abdication in 1936. He was "deeply shocked" by the abdication, not dreaming until it was announced that it would happen, and the evening he heard of it "he was so stunned that he went out and walked 3 times round St James Park in the darkness, thinking of James II." Lascelles became Assistant Private Secretary to George VI, some time after the new king's accession. Lascelles was made a Knight Commander of the
Royal Victorian Order (KCVO) by George VI during the
1939 royal tour of Canada, which he had helped to arrange and manage. The title is an honour given as a personal gift by the sovereign and does not require political approval. He had been appointed a Companion of the Order of the Bath in 1937, was promoted to Knight Commander of the Order of the Bath in 1944, and to Knight Grand Cross on his retirement in 1953. He retired from his 27 years of royal service on the last day of 1953, at the age of 66. He had been asked by then Prime Minister
Sir Winston Churchill twice and by the Queen once whether he would like to go to the
House of Lords with a
hereditary peerage, but he declined. He did, however, accept appointment as a Knight Grand Cross of the
Order of the Bath, which, he said, "rated much higher than a peerage". In 1955, Lascelles was very supportive of
James Pope-Hennessy's commission to write an official biography of Queen Mary, although initially he wondered why and by whom this unknown young writer had been commissioned. Lascelles was a crucial witness for many key events (e.g., the abdication of Edward VIII). When the book passed the royal censors, Lascelles was livid that Pope-Hennessy phoned him with the news rather than coming round with the good news in person. Lascelles's papers are now held in the
Churchill Archives Centre at
Churchill College,
Cambridge. ==Personal life==