diff --git a/lisp/image-dired.el b/lisp/image-dired.el
index f6a263749f..0b357332a1 100644
--- a/lisp/image-dired.el
+++ b/lisp/image-dired.el
@@ -117,8 +117,6 @@
 ;; * From thumbs.el: Add an option for clean-up/max-size functionality
 ;;   for thumbnail directory.
 ;;
-;; * From thumbs.el: Add setroot function.
-;;
 ;; * From thumbs.el: Add image resizing, if useful (image-dired's automatic
 ;;  "image fit" might be enough)
 ;;
@@ -2818,6 +2816,71 @@ image-dired-save-information-from-widgets
        (dolist (tag tag-list)
          (push (cons file tag) lst))))))
 
+
+;;;; Setting background.
+
+(defcustom image-dired-set-background-program
+  (cond ((executable-find "feh") "feh")
+        ((executable-find "gm") "gm")
+        ((executable-find "display") "display")
+        ((executable-find "xloadimage") "xloadimage")
+        ((executable-find "xsetbg") "xsetbg"))
+  "Command to set the desktop background.
+You must also set `image-dired-cmd-set-background-options' or
+this will not work.
+
+Note: If you find that you need to use a different command on
+your machine, we would like to hear about it!  Please send an
+email to bug-gnu-emacs@gnu.org and tell us which
+command (including all options) that worked for you."
+  :type 'string
+  :version "29.1")
+
+(defcustom image-dired-cmd-set-background-options
+  (cond ((executable-find "feh") '("--bg-scale" "%f"))
+        ((executable-find "gm") '("display" "-resize" "%wx%h" "-window" "root" "%f"))
+        ((executable-find "display") '("-resize" "%wx%h" "-window" "root" "%f"))
+        ((executable-find "xloadimage") '("-onroot" "-fullscreen" "%f"))
+        ((executable-find "xsetbg") '"%f"))
+  "Options to pas to the program setting the desktop background.
+The default scales the image to fit the background.
+
+To see which options are available, see the documentation for
+your chosen `image-dired-cmd-set-background-program'."
+  :type '(repeat string)
+  :version "29.1")
+
+(defun image-dired-set-desktop-background (file)
+  "Set the desktop background to FILE in a graphical environment."
+  (interactive (list (or (image-dired-original-file-name)
+                         (read-file-name "Set desktop background to:"
+                                         default-directory nil t nil
+                                         (lambda (fn)
+                                           (string-match (image-file-name-regexp) fn))))))
+  (when (display-graphic-p)
+    (let* ((spec `((?f . ,file)
+                   (?h . ,(display-pixel-height))
+                   (?w . ,(display-pixel-width))))
+           (buf (format " *desktop-background-%s*"
+                        (random)))
+           (process
+            (apply #'start-process "set-desktop-background" buf
+                   image-dired-cmd-set-background-program
+                   (mapcar (lambda (arg) (format-spec arg spec))
+                           image-dired-cmd-set-background-options))))
+      (setf (process-sentinel process)
+            (lambda (process status)
+              (unwind-protect
+                  (unless (and (eq (process-status process) 'exit)
+                               (zerop (process-exit-status process)))
+                    (message "command %S %s: %S" (string-join (process-command process) " ")
+                             (string-replace "\n" "" status)
+                             (with-current-buffer (process-buffer process)
+                               (string-clean-whitespace (buffer-string)))))
+                (ignore-errors
+                  (kill-buffer (process-buffer process))))))
+      process)))
+
 
 ;;;; bookmark.el support