diff --git a/lib/groupdate/magic.rb b/lib/groupdate/magic.rb
index 49080f1..e73aa4a 100644
--- a/lib/groupdate/magic.rb
+++ b/lib/groupdate/magic.rb
@@ -245,7 +245,7 @@ module Groupdate
               when :month_of_year
                 key = Date.new(2014, key, 1).to_time
               end
-              I18n.localize(key, format: options[:format].to_s)
+              I18n.localize(key, format: options[:format].to_s, locale: I18n.locale)
             end
           end
         else
--
libgit2 0.21.0