Rex Stout's liberal activism earned him the ire of prominent conservatives. When the anti-Communist hysteria of the late 1940s and 1950s began, Stout found himself targeted by members of the American Legion. He ignored a subpoena from the House Un-American Activities Committee at the height of the McCarthy era.
He served from 1906 to 1908 in the U.S. Navy, as a yeoman on President Theodore Roosevelt's official yacht.
The Nero Wolfe corpus was nominated Best Mystery Series of the Century at Bouchercon 2000, the world's largest mystery convention, and Rex Stout was nominated Best Mystery Writer of the Century.
Rex Stout served on the original board of the American Civil Liberties Union.