diff --git a/core/modules/language/language.module b/core/modules/language/language.module
index 1dabc31..3eb5f52 100644
--- a/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -288,7 +288,7 @@ function language_configuration_element_submit(&$form, &$form_state) {
 }
 
 /**
- * Saves a language configuration that is attached to a bundle or entity type.
+ * Saves a language configuration that is attached to an entity type and bundle.
  *
  * @param string $entity_type
  *   A string representing the entity type.
@@ -304,7 +304,7 @@ function language_save_default_configuration($entity_type, $bundle,  $values = a
 }
 
 /**
- * Returns the language configuration stored for an entity type (and bundle).
+ * Returns the language configuration stored for an entity type and bundle.
  *
  * @param string $entity_type
  *   A string representing the entity type.
@@ -325,6 +325,18 @@ function language_get_default_configuration($entity_type, $bundle) {
 }
 
 /**
+ * Clears the default language configuration for an entity type and bundle.
+ *
+ * @param string $entity_type
+ *   A string representing the entity type.
+ * @param string $bundle
+ *   A string representing the bundle.
+ */
+function language_clear_default_configuration($entity_type, $bundle) {
+  config('language.settings')->clear(language_get_default_configuration_settings_path($entity_type, $bundle))->save();
+}
+
+/**
  * Returns the root name of the variables used to store the configuration.
  *
  * Based on the entity type (and if needed, bundle), the variables used to store
@@ -385,7 +397,7 @@ function language_get_default_langcode($entity_type, $bundle) {
   }
   // If we did not found a default value so far, invoke all other modules that
   // may provide a special default language.
-  $default_value = module_invoke_all('language_default_langcode', $entity_type, $bundle);
+  $default_value = module_invoke_all('language_default_langcode', $entity_type, $bundle, $configuration);
   $default_value = array_shift($default_value);
   if ($default_value) {
     return $default_value;
diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationElementTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationElementTest.php
index 6ad3786..c9f4102 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationElementTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageConfigurationElementTest.php
@@ -8,6 +8,7 @@
 namespace Drupal\language\Tests;
 
 use Drupal\simpletest\WebTestBase;
+use Drupal\Core\Language\Language;
 
 /**
  * Functional tests for language configuration's effect on negotiation setup.
@@ -38,6 +39,9 @@ class LanguageConfigurationElementTest extends WebTestBase {
     // Check that the settings have been saved.
     $this->assertEqual($lang_conf['language'], 'current_interface');
     $this->assertTrue($lang_conf['language_hidden']);
+    $this->drupalGet('language-tests/language_configuration_element');
+    $this->assertOptionSelected('edit-lang-configuration-language', 'current_interface');
+    $this->assertFieldChecked('edit-lang-configuration-language-hidden');
 
     // Reload the page and save again.
     $this->drupalGet('language-tests/language_configuration_element');
@@ -48,8 +52,53 @@ class LanguageConfigurationElementTest extends WebTestBase {
     // Check that the settings have been saved.
     $this->assertEqual($lang_conf['language'], 'authors_default');
     $this->assertFalse($lang_conf['language_hidden']);
+    $this->drupalGet('language-tests/language_configuration_element');
+    $this->assertOptionSelected('edit-lang-configuration-language', 'authors_default');
+    $this->assertNoFieldChecked('edit-lang-configuration-language-hidden');
+  }
+
+  /**
+   * Tests that the language_get_default_langcode() returns the correct values.
+   */
+  public function testDefaultLangcode() {
+    // Add some custom languages.
+    foreach (array('aa', 'bb', 'cc') as $language_code) {
+      $language = new Language(array(
+        'langcode' => $language_code,
+        'name' => $this->randomName(),
+      ));
+      language_save($language);
+    }
+    // Fixed language.
+    language_save_default_configuration('custom_type', 'custom_bundle', array('language' => 'bb', 'language_hidden' => FALSE));
+    $langcode = language_get_default_langcode('custom_type', 'custom_bundle');
+    $this->assertEqual($langcode, 'bb');
+
+    // Current interface.
+    language_save_default_configuration('custom_type', 'custom_bundle', array('language' => 'current_interface', 'language_hidden' => FALSE));
+    $langcode = language_get_default_langcode('custom_type', 'custom_bundle');
+    $language_interface = language(LANGUAGE_TYPE_INTERFACE);
+    $this->assertEqual($langcode, $language_interface->langcode);
+
+    // Site's default.
+    $old_default = language_default();
+    $old_default->default = FALSE;
+    language_save($old_default);
+    $new_default = language_load('cc');
+    $new_default->default = TRUE;
+    language_save($new_default);
+    language_save_default_configuration('custom_type', 'custom_bundle', array('language' => 'site_default', 'language_hidden' => FALSE));
+    $langcode = language_get_default_langcode('custom_type', 'custom_bundle');
+    $this->assertEqual($langcode, 'cc');
 
+    // @todo: The language_get_default_langcode() uses the global $user to
+    // return the preferred language, but the global $user is not the logged
+    // in user from the simpletest browser...
 
-    // @todo: check also the interface and write more tests.
+    // Some custom language code, hook_language_default_langcode() is
+    // implemented in the language_elements_test module.
+    language_save_default_configuration('custom_type', 'custom_bundle', array('language' => 'custom_code', 'language_hidden' => FALSE));
+    $langcode = language_get_default_langcode('custom_type', 'custom_bundle');
+    $this->assertEqual($langcode, 'custom_value');
   }
 }
diff --git a/core/modules/language/tests/language_elements_test/language_elements_test.module b/core/modules/language/tests/language_elements_test/language_elements_test.module
index 5e43165..2b80796 100644
--- a/core/modules/language/tests/language_elements_test/language_elements_test.module
+++ b/core/modules/language/tests/language_elements_test/language_elements_test.module
@@ -38,3 +38,12 @@ function language_elements_test_configuration_element() {
   $form['#submit'][] = 'language_configuration_element_submit';
   return $form;
 }
+
+/**
+ * Implements hook_language_default_langcode().
+ */
+function language_elements_test_language_default_langcode($entity_type, $bundle, $configuration) {
+  if ($entity_type == 'custom_type' && $bundle == 'custom_bundle' && $configuration['language'] == 'custom_code') {
+    return 'custom_value';
+  }
+}
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermLanguageTest.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermLanguageTest.php
index 4e6878b..c8e2222 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermLanguageTest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermLanguageTest.php
@@ -33,22 +33,18 @@ class TermLanguageTest extends TaxonomyTestBase {
 
     // Create a vocabulary to which the terms will be assigned.
     $this->vocabulary = $this->createVocabulary();
+
+    // Add some custom languages.
+    foreach (array('aa', 'bb', 'cc') as $language_code) {
+      $language = new Language(array(
+        'langcode' => $language_code,
+        'name' => $this->randomName(),
+      ));
+      language_save($language);
+    }
   }
 
   function testTermLanguage() {
-    // Add first some custom languages.
-    $language = new Language(array(
-      'langcode' => 'aa',
-      'name' => $this->randomName(),
-    ));
-    language_save($language);
-
-    $language = new Language(array(
-      'langcode' => 'bb',
-      'name' => $this->randomName(),
-    ));
-    language_save($language);
-
     // Configure the vocabulary to not hide the language selector.
     $edit = array(
       'default_language[language_hidden]' => FALSE,
@@ -81,4 +77,43 @@ class TermLanguageTest extends TaxonomyTestBase {
     $this->drupalGet('taxonomy/term/' . $term->tid . '/edit');
     $this->assertOptionSelected('edit-langcode', $edit['langcode'], t('The term language was correctly selected.'));
   }
+
+  function testDefaultTermLanguage() {
+    // Configure the vocabulary to not hide the language selector, and make the
+    // default language of the terms fixed.
+    $edit = array(
+      'default_language[language]' => 'bb',
+      'default_language[language_hidden]' => FALSE,
+    );
+    $this->drupalPost('admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/edit', $edit, t('Save'));
+    $this->drupalGet('admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/add');
+    $this->assertOptionSelected('edit-langcode', 'bb');
+
+    // Make the default language of the terms to be the current interface.
+    $edit = array(
+      'default_language[language]' => 'current_interface',
+      'default_language[language_hidden]' => FALSE,
+    );
+    $this->drupalPost('admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/edit', $edit, t('Save'));
+    $this->drupalGet('aa/admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/add');
+    $this->assertOptionSelected('edit-langcode', 'aa');
+    $this->drupalGet('bb/admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/add');
+    $this->assertOptionSelected('edit-langcode', 'bb');
+
+    // Change the default language of the site and check if the default terms
+    // language is still correctly selected.
+    $old_default = language_default();
+    $old_default->default = FALSE;
+    language_save($old_default);
+    $new_default = language_load('cc');
+    $new_default->default = TRUE;
+    language_save($new_default);
+    $edit = array(
+      'default_language[language]' => 'site_default',
+      'default_language[language_hidden]' => FALSE,
+    );
+    $this->drupalPost('admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/edit', $edit, t('Save'));
+    $this->drupalGet('admin/structure/taxonomy/' . $this->vocabulary->machine_name . '/add');
+    $this->assertOptionSelected('edit-langcode', 'cc');
+  }
 }
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/VocabularyLanguageTest.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/VocabularyLanguageTest.php
index f4368b7..47b174d 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/VocabularyLanguageTest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/VocabularyLanguageTest.php
@@ -30,10 +30,8 @@ class VocabularyLanguageTest extends TaxonomyTestBase {
     // Create an administrative user.
     $this->admin_user = $this->drupalCreateUser(array('administer taxonomy'));
     $this->drupalLogin($this->admin_user);
-  }
 
-  function testVocabularyLanguage() {
-    // Add first some custom languages.
+    // Add some custom languages.
     $language = new Language(array(
       'langcode' => 'aa',
       'name' => $this->randomName(),
@@ -45,7 +43,9 @@ class VocabularyLanguageTest extends TaxonomyTestBase {
       'name' => $this->randomName(),
     ));
     language_save($language);
+  }
 
+  function testVocabularyLanguage() {
     $this->drupalGet('admin/structure/taxonomy/add');
     // Check that we have the language selector available.
     $this->assertField('edit-langcode', t('The language selector field was found on the page'));
@@ -70,4 +70,62 @@ class VocabularyLanguageTest extends TaxonomyTestBase {
     $this->drupalGet('admin/structure/taxonomy/' . $machine_name . '/edit');
     $this->assertOptionSelected('edit-langcode', $edit['langcode'], t('The vocabulary language was correctly selected.'));
   }
+
+  function testVocabularyDefaultLanguageForTerms() {
+    // Add a new vocabulary and check that the default language settings are for
+    // the terms are saved.
+    $edit = array(
+      'name' => $this->randomName(),
+      'machine_name' => drupal_strtolower($this->randomName()),
+      'default_language[language]' => 'bb',
+      'default_language[language_hidden]' => FALSE,
+    );
+    $machine_name = $edit['machine_name'];
+    $this->drupalPost('admin/structure/taxonomy/add', $edit, t('Save'));
+    // Check that the vocabulary was actually created.
+    $this->drupalGet('admin/structure/taxonomy/' . $edit['machine_name'] . '/edit');
+    $this->assertResponse(200, 'The vocabulary has been created.');
+
+    // Check that the language settings were saved.
+    $language_settings = language_get_default_configuration('vocabulary', $edit['machine_name']);
+    $this->assertEqual($language_settings['language'], 'bb');
+    $this->assertEqual($language_settings['language_hidden'], FALSE);
+
+    // Check that the correct options are selected in the interface.
+    $this->assertOptionSelected('edit-default-language-language', 'bb', 'The correct default language for the terms of this vocabulary is selected.');
+    $this->assertNoFieldChecked('edit-default-language-language-hidden', 'Hide language selection option is not checked.');
+
+    // Edit the vocabulary and check that the new settings are updated.
+    $edit = array(
+      'default_language[language]' => 'aa',
+      'default_language[language_hidden]' => TRUE,
+    );
+    $this->drupalPost('admin/structure/taxonomy/' . $machine_name . '/edit', $edit, t('Save'));
+
+    // And check again the settings and also the interface.
+    $language_settings = language_get_default_configuration('vocabulary', $machine_name);
+    $this->assertEqual($language_settings['language'], 'aa');
+    $this->assertEqual($language_settings['language_hidden'], TRUE);
+
+    $this->drupalGet('admin/structure/taxonomy/' . $machine_name . '/edit');
+    $this->assertOptionSelected('edit-default-language-language', 'aa', 'The correct default language for the terms of this vocabulary is selected.');
+    $this->assertFieldChecked('edit-default-language-language-hidden', 'Hide language selection option is not checked.');
+
+    // Check that, if the machine name of the vocabulary is changed, then the
+    // settings are applied on the new machine name.
+     $edit = array(
+      'machine_name' => $machine_name . '_new',
+      'default_language[language]' => 'authors_default',
+      'default_language[language_hidden]' => TRUE,
+    );
+    $new_machine_name = $edit['machine_name'];
+    $this->drupalPost('admin/structure/taxonomy/' . $machine_name . '/edit', $edit, t('Save'));
+    // Check that the the old settings are empty.
+    $old_settings = config('language.settings')->get(language_get_default_configuration_settings_path('vocabulary', $machine_name));
+    $this->assertNull($old_settings, 'The old vocabulary settings were deleted.');
+    // Check that we have the new settings.
+    $new_settings = language_get_default_configuration('vocabulary', $new_machine_name);
+    $this->assertEqual($new_settings['language'], 'authors_default');
+    $this->assertEqual($new_settings['language_hidden'], TRUE);
+  }
 }
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/VocabularyFormController.php b/core/modules/taxonomy/lib/Drupal/taxonomy/VocabularyFormController.php
index 410a75a..0e6cbc2 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/VocabularyFormController.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/VocabularyFormController.php
@@ -124,6 +124,12 @@ class VocabularyFormController extends EntityFormController {
    *
    */
   public function languageConfigurationSubmit(array &$form, array &$form_state) {
+    $vocabulary = $this->getEntity($form_state);
+    // Delete the old language settings for the vocabulary, if the machine name
+    // is changed.
+    if ($vocabulary && isset($vocabulary->machine_name) && $vocabulary->machine_name != $form_state['values']['machine_name']) {
+      language_clear_default_configuration('vocabulary', $vocabulary->machine_name);
+    }
     // Because the bundle is not yet known and moreover, it can be changed for a
     // vocabulary, we have to also update the language_configuration_elements in
     // order to have the correct bundle value.