diff --git a/lisp/calendar/holidays.el b/lisp/calendar/holidays.el
index 18a24352749..cee571f5f1c 100644
--- a/lisp/calendar/holidays.el
+++ b/lisp/calendar/holidays.el
@@ -488,6 +488,9 @@ is non-nil)."
        (list (list (calendar-gregorian-from-absolute (+ abs-easter n))
                    string))))))
 
+;; Prior call to calendar-julian-from-absolute will autoload cal-julian.
+(declare-function calendar-absolute-from-julian "cal-julian" (date))
+
 (defun holiday-greek-orthodox-easter ()
   "Date of Easter according to the rule of the Council of Nicaea."
   (let ((m displayed-month)