An Armenian, born Dikran Kouyoumdjian in Bulgaria, Arlen became a popular writer in England in the '20s (Wikipedia, Tartarus).
After coming to England to complete his education, Kouyoumdjian adopted the name Michael Arien following his decision to become a British citizen and pursue a literary career. Although Arlen published his first book at the early age of eighteen, it was not until eleven years later that he achieved real success with *The Green Hat* (1924). A fashionable series of best-selling society novels and short stories followed, perfectly capturing the hedonistic spirit of the times. Arlen eventually married into the English upper-class society he so often satirised and moved first to France and later to Hollywood to develop his career.
Among his fictional works, Arlen wrote a number of supernatural pieces which demonstrate a variety of literary infuences ranging from Saki and Oscar Wilde to Arthur Machen.
[Source: *Shadows in the Attic: A Guide to British Supernatural Fiction 1820-1950*, Neil Wilson (2000).]
Michael J Arlen, who also appears in Open Library (here) is probably the son mentioned in the Wikipedia link.
