diff --git a/mkdocs/themes/mkdocs/js/base.js b/mkdocs/themes/mkdocs/js/base.js
index 16962b3527..6b00749a93 100644
--- a/mkdocs/themes/mkdocs/js/base.js
+++ b/mkdocs/themes/mkdocs/js/base.js
@@ -20,6 +20,10 @@ $(document).ready(function() {
         $search_modal = $('#mkdocs_search_modal'),
         $keyboard_modal = $('#mkdocs_keyboard_modal');
 
+    // Make base_url global, so external scripts can find it
+    //  (e.g. the search plugin)
+    window.base_url = base_url;
+
     if(highlightjs) {
         hljs.initHighlightingOnLoad();
     }