diff --git a/core/modules/entity/entity.module b/core/modules/entity/entity.module
index 74f2fcf..c63b2f8 100644
--- a/core/modules/entity/entity.module
+++ b/core/modules/entity/entity.module
@@ -467,12 +467,13 @@ function entity_form_id(EntityInterface $entity, $operation = 'default') {
  * @return
  *   A $form_state array already filled the entity form controller.
  */
-function entity_form_state_defaults(EntityInterface $entity, $operation = 'default') {
+function entity_form_state_defaults(EntityInterface $entity, $operation = 'default', $langcode = NULL) {
   $form_state = array();
   $controller = entity_form_controller($entity->entityType(), $operation);
   $form_state['build_info']['callback'] = array($controller, 'build');
   $form_state['build_info']['base_form_id'] = $entity->entityType() . '_form';
   $form_state['build_info']['args'] = array($entity);
+  $form_state['langcode'] = $langcode;
   return $form_state;
 }
 
@@ -506,8 +507,8 @@ function entity_form_submit(EntityInterface $entity, $operation = 'default', &$f
  * @return
  *   The processed form for the given entity and operation.
  */
-function entity_get_form(EntityInterface $entity, $operation = 'default') {
-  $form_state = entity_form_state_defaults($entity, $operation);
+function entity_get_form(EntityInterface $entity, $operation = 'default', $langcode = NULL) {
+  $form_state = entity_form_state_defaults($entity, $operation, $langcode);
   $form_id = entity_form_id($entity, $operation);
   return drupal_build_form($form_id, $form_state);
 }
diff --git a/core/modules/entity/lib/Drupal/entity/EntityFormController.php b/core/modules/entity/lib/Drupal/entity/EntityFormController.php
index 4f1263c..72c01de 100644
--- a/core/modules/entity/lib/Drupal/entity/EntityFormController.php
+++ b/core/modules/entity/lib/Drupal/entity/EntityFormController.php
@@ -208,11 +208,26 @@ class EntityFormController implements EntityFormControllerInterface {
    * Implements Drupal\entity\EntityFormControllerInterface::getFormLangcode().
    */
   public function getFormLangcode($form_state) {
-    // @todo Introduce a new form language type (see hook_language_types_info())
-    // to be used as the default active form language, should it be missing, so
-    // that entity forms can be used to submit multilingual values.
-    $language = $this->getEntity($form_state)->language();
-    return !empty($language->langcode) ? $language->langcode : NULL;
+    $entity = $this->getEntity($form_state);
+    $translations = $entity->translations();
+
+    if (!empty($form_state['langcode'])) {
+      $langcode = $form_state['langcode'];
+    }
+    else {
+      // If no form langcode was provided we default to the current content
+      // language and inspect existing translations to find a valid fallback,
+      // if any.
+      $langcode = language(LANGUAGE_TYPE_CONTENT)->langcode;
+      $fallback = language_multilingual() ? language_fallback_get_candidates() : array();
+      while (!empty($langcode) && !isset($translations[$langcode])) {
+        $langcode = array_shift($fallback);
+      }
+    }
+
+    // If the site is not multilingual or no translation for the given form
+    // language is available, fall back to the entity language.
+    return !empty($langcode) ? $langcode : $entity->language()->langcode;
   }
 
   /**