The narrator, Jake Barnes, opens with a description of a friend of his, Robert Cohn, whose crowning triumph was being named Princeton’s middleweight boxing champion in his college days. Impressive, right?
Right. Jake isn’t terribly impressed, either. Though he’s fond of Cohn, he actually sees the other man as kind of a forgettable wimp. So forgettable, in fact, that Jake is stunned that Cohn’s former boxing coach even remembers him.
Cohn is Jewish, a fact that Jake finds central to his character development. He is innately self-conscious, married young, had an unhappy marriage, and was left by his wife (who he was feebly attempting to leave anyway).
After his divorce, Cohn moved to California, where he briefly edited a magazine. But, he was too poor to fund the publication and it died—the magazine that is. Cohn’s literary ambitions live on.
Cohn now lives in Paris with a forceful divorcée named Frances. Jake is his tennis friend, as compared to Braddocks, who is Cohn’s literary friend (an interesting distinction, considering that Jake is also a writer—the difference is that he’s a journalist).
Cohn is a published novelist, but his writing isn’t highly regarded by Jake or anyone else. Frances, Cohn’s mistress, is a total control freak. In the midst of coffee with Cohn and Frances, Jake’s mere suggestion of traveling with Cohn to visit an American woman earns him a swift "shut-up!" kick from Cohn. Clearly, any mention of other women is strictly off-limits in Frances’s vicinity.
Jake is bemused by Cohn’s weakness, especially with women.