diff --git a/mu4e/mu4e.el b/mu4e/mu4e.el
index d0a4dcce..5389dec8 100644
--- a/mu4e/mu4e.el
+++ b/mu4e/mu4e.el
@@ -72,11 +72,12 @@
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;###autoload
-(defun mu4e ()
-  "Start mu4e."
-  (interactive)
+(defun mu4e (&optional background)
+  "If mu4e is not running yet, start it. Then, show the the main
+window, unless BACKGROUND (prefix-argument) is non-nil."
+  (interactive "P")
   ;; start mu4e, then show the main view
-  (mu4e~start 'mu4e~main-view))
+  (mu4e~start (unless background 'mu4e~main-view)))
 
 (defun mu4e-quit()
   "Quit the mu4e session."