He wrote a letter from Cuba to Ballantine Beer. Whoa, ease up on the hyperbole there, Papa.
Why write your own ads when Hemingway writes a better one for you?
Papa actually wrote this sales pitch for Ballantine in 1951:
Bob Benchley (American humorist) first introduced me to Ballantine Ale. It has been a good companion ever since.
You have to work hard to deserve to drink it (sfx: Ballantine CEO squeals with glee). But I would rather have a bottle of Ballantine Ale than any other drink after fighting a really big fish. When something has been taken out of you by strenuous exercise Ballantine puts it back in. (It was Hemingway's Gatorade).
We keep it iced in the bait box with chunks of ice packed around it. And you ought to taste it on a hot day when you have worked a big marlin fast because there were sharks after him. (Got that, you pansy-ass urbanites?)
You are tired all the way through. The fish is landed untouched by sharks and you have a bottle of Ballantine cold in your hand and drink it cool, light, and full-bodied, so it tastes good long after you have swallowed it. That's the test of an ale with me: whether it tastes as good afterwards as when it's going down. Ballantine does.
(Insecure, wimpy New York ad agency copywriter slinks off to the pub to order a Ballantine.)
Well, free hooch is free hooch, and Papa was a performance drinker. And of course, he managed to slip in how awesome of a marlin fisherman he was.
Note: John Steinbeck also appeared in a Ballantine ad, two years later.