diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2914f0fcd..a488fe9cb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,9 @@
 * Normalize xcconfig path when generating includes.  
   [bclymer](https://github.com/bclymer)
 
+* Use modern localization identifier 'en' for the development region.
+  [Steffen Matthischke](https://github.com/heeaad)
+
 ## 1.8.1 (2019-02-19)
 
 ##### Enhancements
diff --git a/lib/xcodeproj/project/object/root_object.rb b/lib/xcodeproj/project/object/root_object.rb
index 9f3abea5e..c17104a90 100644
--- a/lib/xcodeproj/project/object/root_object.rb
+++ b/lib/xcodeproj/project/object/root_object.rb
@@ -34,7 +34,7 @@ class PBXProject < AbstractObject
 
         # @return [String] the development region of the project.
         #
-        attribute :development_region, String, 'English'
+        attribute :development_region, String, 'en'
 
         # @return [String] whether the project has scanned for encodings.
         #
diff --git a/spec/project/object/root_object_spec.rb b/spec/project/object/root_object_spec.rb
index 2392d82d9..09f380e8d 100644
--- a/spec/project/object/root_object_spec.rb
+++ b/spec/project/object/root_object_spec.rb
@@ -24,7 +24,7 @@ module ProjectSpecs
     end
 
     it 'returns the development region' do
-      @root_object.development_region.should == 'English'
+      @root_object.development_region.should == 'en'
     end
 
     it 'returns whether has scanned for encodings' do