diff --git a/core/modules/hal/src/Tests/NormalizeTest.php b/core/modules/hal/src/Tests/NormalizeTest.php
index ee40c25..39678e3 100644
--- a/core/modules/hal/src/Tests/NormalizeTest.php
+++ b/core/modules/hal/src/Tests/NormalizeTest.php
@@ -79,13 +79,13 @@ public function testNormalize() {
         ),
         $relation_uri => array(
           array(
-            'href' => $this->getEntityUri($target_entity_de),
-            'lang' => 'de',
-          ),
-          array(
             'href' => $this->getEntityUri($target_entity_en),
             'lang' => 'en',
           ),
+          array(
+            'href' => $this->getEntityUri($target_entity_de),
+            'lang' => 'de',
+          ),
         ),
       ),
       '_embedded' => array(
@@ -93,7 +93,7 @@ public function testNormalize() {
           array(
             '_links' => array(
               'self' => array(
-                'href' => $this->getEntityUri($target_entity_de),
+                'href' => $this->getEntityUri($target_entity_en),
               ),
               'type' => array(
                 'href' => $type_uri,
@@ -101,15 +101,15 @@ public function testNormalize() {
             ),
             'uuid' => array(
               array(
-                'value' => $target_entity_de->uuid(),
+                'value' => $target_entity_en->uuid(),
               ),
             ),
-            'lang' => 'de',
+            'lang' => 'en',
           ),
           array(
             '_links' => array(
               'self' => array(
-                'href' => $this->getEntityUri($target_entity_en),
+                'href' => $this->getEntityUri($target_entity_de),
               ),
               'type' => array(
                 'href' => $type_uri,
@@ -117,10 +117,10 @@ public function testNormalize() {
             ),
             'uuid' => array(
               array(
-                'value' => $target_entity_en->uuid(),
+                'value' => $target_entity_de->uuid(),
               ),
             ),
-            'lang' => 'en',
+            'lang' => 'de',
           ),
         ),
       ),
@@ -136,13 +136,13 @@ public function testNormalize() {
       ),
       'name' => array(
         array(
-          'value' => $values['name'],
-          'lang' => 'de',
-        ),
-        array(
           'value' => $translation_values['name'],
           'lang' => 'en',
         ),
+        array(
+          'value' => $values['name'],
+          'lang' => 'de',
+        ),
       ),
       'field_test_text' => array(
         array(
diff --git a/core/modules/language/src/ConfigurableLanguageManager.php b/core/modules/language/src/ConfigurableLanguageManager.php
index a4ca11b..98c5ff0 100644
--- a/core/modules/language/src/ConfigurableLanguageManager.php
+++ b/core/modules/language/src/ConfigurableLanguageManager.php
@@ -353,10 +353,11 @@ public function updateLockedLanguageWeights() {
     if (reset($locked_languages)->getWeight() <= $max_weight) {
       foreach ($locked_languages as $language) {
         // Update system languages weight.
-        $max_weight++;
-        ConfigurableLanguage::load($language->getId())
-          ->setWeight($max_weight)
-          ->save();
+        if ($language = ConfigurableLanguage::load($language->getId())) {
+          $max_weight++;
+          $language->setWeight($max_weight)
+            ->save();
+        }
       }
     }
   }
diff --git a/core/modules/language/src/Entity/ConfigurableLanguage.php b/core/modules/language/src/Entity/ConfigurableLanguage.php
index a754654..ecc1e1b 100644
--- a/core/modules/language/src/Entity/ConfigurableLanguage.php
+++ b/core/modules/language/src/Entity/ConfigurableLanguage.php
@@ -121,6 +121,20 @@ public function preSave(EntityStorageInterface $storage) {
     // For the uncommon case of custom languages the label should be given in
     // English.
     $this->langcode = 'en';
+    // When adding a new language the weight shouldn't be zero to avoid a
+    // reordering of the languages list when their names change i.e. interface
+    // translation.
+    // Fetch all configurable languages ordered by weight.
+    $languages = \Drupal::languageManager()->getLanguages($this::STATE_CONFIGURABLE);
+    // Retrieve the last.
+    $last_language = end($languages);
+    // When adding the first Configurable language leave the weight by default.
+    // This happens when you are installing language module.
+    if ($this->isNew() && $last_language->getId() != $this->getId()) {
+      // The newly created language will have the weight of the heaviest
+      // language +1.
+      $this->setWeight($last_language->getWeight() + 1);
+    }
   }
 
   /**
diff --git a/core/modules/language/src/Tests/LanguageListTest.php b/core/modules/language/src/Tests/LanguageListTest.php
index 52f6e4c..d1affab 100644
--- a/core/modules/language/src/Tests/LanguageListTest.php
+++ b/core/modules/language/src/Tests/LanguageListTest.php
@@ -35,6 +35,10 @@ function testLanguageList() {
     $admin_user = $this->drupalCreateUser(array('administer languages', 'access administration pages', 'administer site configuration'));
     $this->drupalLogin($admin_user);
 
+    // Get the weight of the last language.
+    $languages = \Drupal::service('language_manager')->getLanguages();
+    $last_language_weight = end($languages)->getWeight();
+
     // Add predefined language.
     $edit = array(
       'predefined_langcode' => 'fr',
@@ -43,6 +47,14 @@ function testLanguageList() {
     $this->assertText('French', 'Language added successfully.');
     $this->assertUrl(\Drupal::url('entity.configurable_language.collection', [], ['absolute' => TRUE]));
 
+    // Get the weight of the last language and check that the weight is one unit
+    // heavier and that is French.
+    $this->rebuildContainer();
+    $languages = \Drupal::service('language_manager')->getLanguages();
+    $last_language = end($languages);
+    $this->AssertEqual($last_language->getWeight(), $last_language_weight + 1);
+    $this->AssertEqual($last_language->getId(), $edit['predefined_langcode']);
+
     // Add custom language.
     $langcode = 'xx';
     $name = $this->randomMachineName(16);
diff --git a/core/modules/system/src/Tests/Entity/EntityTranslationTest.php b/core/modules/system/src/Tests/Entity/EntityTranslationTest.php
index 6289c03..d91a136 100644
--- a/core/modules/system/src/Tests/Entity/EntityTranslationTest.php
+++ b/core/modules/system/src/Tests/Entity/EntityTranslationTest.php
@@ -504,7 +504,8 @@ protected function doTestLanguageFallback($entity_type) {
     $langcode_key = $this->entityManager->getDefinition($entity_type)->getKey('langcode');
     $languages = $this->languageManager->getLanguages();
     $language = ConfigurableLanguage::load($languages[$langcode]->getId());
-    $language->set('weight', 1);
+    // Make $language the last.
+    $language->set('weight', 4);
     $language->save();
     $this->languageManager->reset();