Some time in the 1920s a Scot called James Alan Rennie went to a Central American country for a petrol company to guard oil wells.
Rennie was a prolific writer of the postwar period, turning out novels, plays, and history books at an industrial rate. In 1962 he wrote his autobiography Past Horizons. Rennie had lived a hell of a life: upbringing in Scotland, youthful service in WWI, art school, prospecting in Canada, travelling through America, nightclub bouncer, logger in the arctic circle. And briefly a mercenary for an oil company.
Rennie passes over the episode in a few pages, careful not to give too much away. He doesn’t tell us the name of the country, the company, or very much about what he did to protect oil wells from revolutionaries.