Sir Dermot MacDermot KCMG CBE^[1] (1906–1989), styled Prince of Coolavin, Chief of the Name, head of the MacDermot clan, and a descendant of the Kings of Moylurg.

MacDermot attended Stonyhurst College,^[2] and went on to Trinity College Dublin, where he was elected a Scholar.^[3]

Sir Dermot MacDermot had served as British Ambassador to Indonesia (1956–59) and Thailand (1961–65). He succeeded his brother as The MacDermot upon the latter's death in 1979. He wrote an account of the family titled "MacDermot of Moylurg: The Story of a Connacht Family". The book chronicles the affairs of the Kings of Moylurg and their neighbours over the course of six hundred years. It contains thirty-five family trees concerning MacDermots and their related families, and ten appendices.^{[citation needed]}

MacDermot died before seeing the book in print, but it was published shortly after by his sons Niall (who succeeded him as Prince of Coolavin) Hugh and Connor.^{[citation needed]}