diff --git a/umap/settings/base.py b/umap/settings/base.py
index a3e148f7703ad4fc7f20f124ec50ee46fbe6ede8..9b92d1461cde59dd7e2ddcb7637b30e5564f0d92 100644
--- a/umap/settings/base.py
+++ b/umap/settings/base.py
@@ -32,7 +32,7 @@ LANGUAGES = (
     ('da', u'Danish'),
     ('ja', u'Japanese'),
     ('lt', u'Lithuanian'),
-    ('cs_CZ', u'Czech'),
+    ('cs-cz', u'Czech'),
 )
 
 # Make this unique, and don't share it with anybody.