diff --git a/core/modules/comment/src/Tests/CommentTestBase.php b/core/modules/comment/src/Tests/CommentTestBase.php
index 05f139d..bb4e55e 100644
--- a/core/modules/comment/src/Tests/CommentTestBase.php
+++ b/core/modules/comment/src/Tests/CommentTestBase.php
@@ -82,7 +82,7 @@ protected function setUp() {
     $this->container->get('comment.manager')->addDefaultField('node', 'article');
 
     // Create a test node authored by the web user.
-    $this->node = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'uid' => $this->web_user->id()));
+    $this->node = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'uid' => $this->web_user->id(), 'langcode' => 'en'));
   }
 
   /**
diff --git a/core/modules/contextual/src/Tests/ContextualDynamicContextTest.php b/core/modules/contextual/src/Tests/ContextualDynamicContextTest.php
index 61fa85e..c4150f3 100644
--- a/core/modules/contextual/src/Tests/ContextualDynamicContextTest.php
+++ b/core/modules/contextual/src/Tests/ContextualDynamicContextTest.php
@@ -50,9 +50,9 @@ function testDifferentPermissions() {
     // - An article, which should be user-editable.
     // - A page, which should not be user-editable.
     // - A second article, which should also be user-editable.
-    $node1 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1));
-    $node2 = $this->drupalCreateNode(array('type' => 'page', 'promote' => 1));
-    $node3 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1));
+    $node1 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'langcode' => 'en'));
+    $node2 = $this->drupalCreateNode(array('type' => 'page', 'promote' => 1, 'langcode' => 'en'));
+    $node3 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'langcode' => 'en'));
 
     // Now, on the front page, all article nodes should have contextual links
     // placeholders, as should the view that contains them.
diff --git a/core/modules/file/src/Tests/FileFieldRSSContentTest.php b/core/modules/file/src/Tests/FileFieldRSSContentTest.php
index db265c2..42b88ce 100644
--- a/core/modules/file/src/Tests/FileFieldRSSContentTest.php
+++ b/core/modules/file/src/Tests/FileFieldRSSContentTest.php
@@ -51,7 +51,7 @@ function testFileFieldRSSContent() {
 
     // Create a new node with a file field set. Promote to frontpage
     // needs to be set so this node will appear in the RSS feed.
-    $node = $this->drupalCreateNode(array('type' => $type_name, 'promote' => 1));
+    $node = $this->drupalCreateNode(array('type' => $type_name, 'promote' => 1, 'langcode' => 'en'));
     $test_file = $this->getTestFile('text');
 
     // Create a new node with the uploaded file.
diff --git a/core/modules/node/src/Tests/NodeLoadMultipleTest.php b/core/modules/node/src/Tests/NodeLoadMultipleTest.php
index 3cea6a1..fbeb16b 100644
--- a/core/modules/node/src/Tests/NodeLoadMultipleTest.php
+++ b/core/modules/node/src/Tests/NodeLoadMultipleTest.php
@@ -31,10 +31,10 @@ protected function setUp() {
    * Creates four nodes and ensures that they are loaded correctly.
    */
   function testNodeMultipleLoad() {
-    $node1 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1));
-    $node2 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1));
-    $node3 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 0));
-    $node4 = $this->drupalCreateNode(array('type' => 'page', 'promote' => 0));
+    $node1 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'langcode' => 'en'));
+    $node2 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'langcode' => 'en'));
+    $node3 = $this->drupalCreateNode(array('type' => 'article', 'promote' => 0, 'langcode' => 'en'));
+    $node4 = $this->drupalCreateNode(array('type' => 'page', 'promote' => 0, 'langcode' => 'en'));
 
     // Confirm that promoted nodes appear in the default node listing.
     $this->drupalGet('node');
diff --git a/core/modules/node/src/Tests/NodeRSSContentTest.php b/core/modules/node/src/Tests/NodeRSSContentTest.php
index e4b7cb3..6a1c830 100644
--- a/core/modules/node/src/Tests/NodeRSSContentTest.php
+++ b/core/modules/node/src/Tests/NodeRSSContentTest.php
@@ -40,7 +40,7 @@ protected function setUp() {
    */
   function testNodeRSSContent() {
     // Create a node.
-    $node = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1));
+    $node = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'langcode' => 'en'));
 
     $this->drupalGet('rss.xml');