diff --git a/mercurial/templatekw.py b/mercurial/templatekw.py
--- a/mercurial/templatekw.py
+++ b/mercurial/templatekw.py
@@ -333,9 +333,9 @@ def showlatesttagdistance(repo, ctx, tem
 
 def showmanifest(**args):
     repo, ctx, templ = args['repo'], args['ctx'], args['templ']
+    mnode = ctx.manifestnode()
     args = args.copy()
-    args.update({'rev': repo.manifest.rev(ctx.changeset()[0]),
-                 'node': hex(ctx.changeset()[0])})
+    args.update({'rev': repo.manifest.rev(mnode), 'node': hex(mnode)})
     return templ('manifest', **args)
 
 def shownode(repo, ctx, templ, **args):