I was curious about the first first song to use a fadeout ending as opposed to coming to a regular cadential close, so I searched to see if the Internet could tell me.

It didn’t take long.

I was surprised to find that Joseph Haydn could be awarded the honors for his Farewell Symphony. And second place goes to Gustav Holst for the “Neptune” movement of his The Planets suite:

When it was first staged in 1914, a female chorus was placed in a room to the side of the stage. As the suite began to wrap up, the door was slowly closed, making it harder and harder for the audience to hear them. Everything came to an end when the chorus appeared to fade into silence.

But what about the first pop song? That’s what I was really looking for.

The article “Why do some songs fade out? The history behind it: Alan Cross” offers a good theory.