Guys and Dolls opened on Broadway in November 1950 with a joke built right into its premise: a gambler bets he can talk a straitlaced mission sergeant into dinner in Havana. The sergeant, Sarah Brown, runs something called the Save-a-Soul Mission, and audiences in 1950 did not need the connection explained to them. They knew exactly what kind of organization they were watching get satirized, tambourines, street corner hymns and all.
The Salvation Army has never pretended otherwise. Its own UK magazine, War Cry, describes the Save-a-Soul Mission plainly as "a movement based on The Salvation Army," and an independent literary history of the show goes further, calling Sergeant Sarah Brown's military rank "an obvious reference to the Salvation Army" in its own right. Neither reading is a stretch. Frank Loesser's score gives the mission a full evangelistic set piece, "Follow the Fold," complete with the kind of brass and testimony that made the Army instantly recognizable on 1950s American streets.
What is easy to miss is that the mission's name did not start with the musical. Damon Runyon had already called it "the Save-a-Soul Mission" in his 1933 short story "The Idyll of Miss Sarah Brown," the tale that gave the show its central romance. Read Runyon's own text closely, though, and the words "Salvation Army" never actually appear in it. Runyon built a Salvation-Army-shaped mission without naming the Army outright, and it was left to seventeen years of audiences, and eventually the Army itself, to say plainly what he had only implied.