Answer
Major Rinaldi is a main character in Ernest Hemingway's novel A Farewell to Arms, on which the 1957 movie is based. Rinaldi plays a crucial role in the protagonist's, Frederic Henry, personal, professional, and romantic developments within the story. He symbolizes Frederic's guide to manhood and provides a perspective external to Frederic's love obsession with the female protagonist, Catherine Barkley.