The 39-year-old has worked at Conde Nast's GQ magazine since its launch nearly 10 years ago and is acknowledged as a leading British commentator on male fashion, social behaviour and lifestyle.
A frequent broadcaster on correct form and dress, his editorship of Debrett's New Guide to Etiquette and Modern Manners has also established him as an authority on matters of taste.
"Morgan's Modern Manners", his weekly column in The Times, gives advice to readers worried about whether a man should help a woman with her chair at dinner or how many kisses to give a stranger.
With an apartment in the Albany, the exclusive block off Piccadilly in central London, he certainly lives the life of gentle sophistication about which he regularly writes.
Mr Morgan, who is always immaculately dressed in a Savile Row suit and silk tie, is seen by friends as a "Burlington Bertie" figure from a bygone age, cashing cheques in Claridges and living the life of a foppish English gentleman.
His image as a friend to minor royals and the landed gentry belies a finely attuned business sense and he is believed to make substantial sums from advising leading companies and their directors on personal manners and style.
And as one colleague said: "The main thing about John is his sense of discretion. He wouldn't tell a soul about Hague's inner secrets."