While it’s probably common knowledge among older aficionados of the literary 007 (and the topic was discussed many moons ago in the old CBN forum), younger readers with an interest in tracing Fleming’s literary influences may not be familiar with the work of his contemporary, author Dennis Wheatley.
Though known primarily for his Black Magic novels such as The Devil Rides Out, the prolific Wheatley also wrote a series of bestsellers whose wartime secret agent protagonist, Gregory Sallust, shares so many attributes with James Bond as to make him 007’s closest literary antecedent.
For anyone who may be interested, I would recommend this excellent exploration of the topic by espionage author Jeremy Duns:
DN