diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index fee191a..c700848 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -740,7 +740,7 @@ function drupal_bootstrap($phase = NULL) {
  * Returns the time zone of the current user.
  */
 function drupal_get_user_timezone() {
-  global $user;
+  $user = \Drupal::currentUser();
   $config = \Drupal::config('system.date');
 
   if ($user && $config->get('timezone.user.configurable') && $user->isAuthenticated() && $user->getTimezone()) {
diff --git a/core/lib/Drupal/Core/Authentication/AuthenticationManager.php b/core/lib/Drupal/Core/Authentication/AuthenticationManager.php
index c4c1df4..3bc40d8 100644
--- a/core/lib/Drupal/Core/Authentication/AuthenticationManager.php
+++ b/core/lib/Drupal/Core/Authentication/AuthenticationManager.php
@@ -85,8 +85,6 @@ public function applies(Request $request) {
    * {@inheritdoc}
    */
   public function authenticate(Request $request) {
-    global $user;
-
     $account = NULL;
 
     // Iterate the allowed providers.
@@ -114,11 +112,6 @@ public function authenticate(Request $request) {
     //  for later access.
     $request->attributes->set('_authentication_provider', $this->triggeredProviderId);
 
-    // The global $user object is included for backward compatibility only and
-    // should be considered deprecated.
-    // @todo Remove this line once global $user is no longer used.
-    $user = $account;
-
     return $account;
   }
 
diff --git a/core/lib/Drupal/Core/Cache/TimeZoneCacheContext.php b/core/lib/Drupal/Core/Cache/TimeZoneCacheContext.php
index 50c4676..ae0621c 100644
--- a/core/lib/Drupal/Core/Cache/TimeZoneCacheContext.php
+++ b/core/lib/Drupal/Core/Cache/TimeZoneCacheContext.php
@@ -10,7 +10,7 @@
 /**
  * Defines the TimeZoneCacheContext service, for "per time zone" caching.
  *
- * @see \Drupal\Core\Session\SessionManager::initialize()
+ * @see \Drupal\Core\Session\AccountProxy::setAccount()
  */
 class TimeZoneCacheContext implements CacheContextInterface {
 
@@ -25,7 +25,7 @@ public static function getLabel() {
    * {@inheritdoc}
    */
   public function getContext() {
-    // date_default_timezone_set() is called in SessionManager::initialize(), so
+    // date_default_timezone_set() is called in AccountProxy::setAccount(), so
     // we can safely retrieve the timezone.
     return date_default_timezone_get();
   }
diff --git a/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php b/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
index e032ab1..b1639ec 100644
--- a/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
+++ b/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
@@ -66,11 +66,6 @@ public function enhance(array $defaults, Request $request) {
         $anonymous_user = new AnonymousUserSession();
 
         $this->currentUser->setAccount($anonymous_user);
-
-        // The global $user object is included for backward compatibility only
-        // and should be considered deprecated.
-        // @todo Remove this line once global $user is no longer used.
-        $GLOBALS['user'] = $anonymous_user;
       }
     }
     return $defaults;
diff --git a/core/lib/Drupal/Core/Session/AccountProxy.php b/core/lib/Drupal/Core/Session/AccountProxy.php
index f9d0d35..e7dc1c3 100644
--- a/core/lib/Drupal/Core/Session/AccountProxy.php
+++ b/core/lib/Drupal/Core/Session/AccountProxy.php
@@ -67,6 +67,8 @@ public function setAccount(AccountInterface $account) {
       $account = $account->getAccount();
     }
     $this->account = $account;
+    // @todo Find a better place to call https://www.drupal.org/node/2427077
+    date_default_timezone_set(drupal_get_user_timezone());
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Session/SessionHandler.php b/core/lib/Drupal/Core/Session/SessionHandler.php
index f46794f..e3b90ce 100644
--- a/core/lib/Drupal/Core/Session/SessionHandler.php
+++ b/core/lib/Drupal/Core/Session/SessionHandler.php
@@ -108,7 +108,7 @@ public function read($sid) {
    * {@inheritdoc}
    */
   public function write($sid, $value) {
-    global $user;
+    $user = \Drupal::currentUser();
 
     // The exception handler is not active at this point, so we need to do it
     // manually.
@@ -155,17 +155,17 @@ public function close() {
    * {@inheritdoc}
    */
   public function destroy($sid) {
-    global $user;
+
 
     // Delete session data.
     $this->connection->delete('sessions')
       ->condition('sid', Crypt::hashBase64($sid))
       ->execute();
 
-    // Reset $_SESSION and $user to prevent a new session from being started
-    // in \Drupal\Core\Session\SessionManager::save().
+    // Reset $_SESSION and current user to prevent a new session from being
+    // started in \Drupal\Core\Session\SessionManager::save().
     $_SESSION = array();
-    $user = new AnonymousUserSession();
+    \Drupal::currentUser()->setAccount(new AnonymousUserSession());
 
     // Unset the session cookies.
     $this->deleteCookie($this->getName());
diff --git a/core/lib/Drupal/Core/Session/SessionManager.php b/core/lib/Drupal/Core/Session/SessionManager.php
index 8249805..8beb132 100644
--- a/core/lib/Drupal/Core/Session/SessionManager.php
+++ b/core/lib/Drupal/Core/Session/SessionManager.php
@@ -146,7 +146,6 @@ public function start() {
 
       $result = FALSE;
     }
-    date_default_timezone_set(drupal_get_user_timezone());
 
     return $result;
   }
@@ -181,7 +180,7 @@ protected function startNow() {
    * {@inheritdoc}
    */
   public function save() {
-    global $user;
+    $user = \Drupal::currentUser();
 
     if ($this->isCli()) {
       // We don't have anything to do if we are not allowed to save the session.
@@ -212,7 +211,7 @@ public function save() {
    * {@inheritdoc}
    */
   public function regenerate($destroy = FALSE, $lifetime = NULL) {
-    global $user;
+    $user = \Drupal::currentUser();
 
     // Nothing to do if we are not allowed to change the session.
     if ($this->isCli()) {
@@ -241,13 +240,8 @@ public function regenerate($destroy = FALSE, $lifetime = NULL) {
 
     if (!$this->isStarted()) {
       // Start the session when it doesn't exist yet.
-      // Preserve the logged in user, as it will be reset to anonymous
-      // by \Drupal\Core\Session\SessionHandler::read().
-      $account = $user;
       $this->startNow();
-      $user = $account;
     }
-    date_default_timezone_set(drupal_get_user_timezone());
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Session/SessionManagerInterface.php b/core/lib/Drupal/Core/Session/SessionManagerInterface.php
index fad62b7..b14b056 100644
--- a/core/lib/Drupal/Core/Session/SessionManagerInterface.php
+++ b/core/lib/Drupal/Core/Session/SessionManagerInterface.php
@@ -38,7 +38,7 @@ public function isEnabled();
    *
    * This function allows the caller to temporarily disable writing of
    * session data, should the request end while performing potentially
-   * dangerous operations, such as manipulating the global $user object.
+   * dangerous operations, such as manipulating the current user.
    *
    * @see https://drupal.org/node/218104
    *
diff --git a/core/modules/basic_auth/src/Authentication/Provider/BasicAuth.php b/core/modules/basic_auth/src/Authentication/Provider/BasicAuth.php
index de41c44..2fed1ed 100644
--- a/core/modules/basic_auth/src/Authentication/Provider/BasicAuth.php
+++ b/core/modules/basic_auth/src/Authentication/Provider/BasicAuth.php
@@ -138,7 +138,7 @@ public function cleanup(Request $request) {}
    */
   public function handleException(GetResponseForExceptionEvent $event) {
     $exception = $event->getException();
-    if ($GLOBALS['user']->isAnonymous() && $exception instanceof AccessDeniedHttpException) {
+    if (\Drupal::currentUser()->isAnonymous() && $exception instanceof AccessDeniedHttpException) {
       if (!$this->applies($event->getRequest())) {
         $site_name = $this->configFactory->get('system.site')->get('name');
         global $base_url;
diff --git a/core/modules/system/src/Tests/Datetime/DrupalDateTimeTest.php b/core/modules/system/src/Tests/Datetime/DrupalDateTimeTest.php
index 29fec17..44144ef 100644
--- a/core/modules/system/src/Tests/Datetime/DrupalDateTimeTest.php
+++ b/core/modules/system/src/Tests/Datetime/DrupalDateTimeTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\simpletest\WebTestBase;
 use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\user\Entity\User;
 
 /**
  * Tests DrupalDateTime functionality.
@@ -51,8 +52,6 @@ public function testSystemTimezone() {
    * stated timezones.
    */
   public function testDateTimezone() {
-    global $user;
-
     $date_string = '2007-01-31 21:00:00';
 
     // Make sure no site timezone has been set.
@@ -93,28 +92,14 @@ public function testDateTimezone() {
     $edit = array('mail' => $test_user->getEmail(), 'timezone' => 'Asia/Manila');
     $this->drupalPostForm('user/' . $test_user->id() . '/edit', $edit, t('Save'));
 
-    // Disable session saving as we are about to modify the global $user.
-    \Drupal::service('session_manager')->disable();
-    // Save the original user and then replace it with the test user.
-    $real_user = $user;
-    $user = user_load($test_user->id(), TRUE);
-
-    // Simulate a Drupal bootstrap with the logged-in user.
-    date_default_timezone_set(drupal_get_user_timezone());
+    \Drupal::entityManager()->getStorage('user')->resetCache();
+    $this->container->get('current_user')->setAccount(User::load($test_user->id()));
 
     // Create a date object with an unspecified timezone, which should
     // end up using the user timezone.
-
     $date = new DrupalDateTime($date_string);
     $timezone = $date->getTimezone()->getName();
     $this->assertTrue($timezone == 'Asia/Manila', 'DrupalDateTime uses the user timezone, if configurable timezones are used and it is set.');
-
-    // Restore the original user, and enable session saving.
-    $user = $real_user;
-    // Restore default time zone.
-    date_default_timezone_set(drupal_get_user_timezone());
-    \Drupal::service('session_manager')->enable();
-
-
   }
+
 }
diff --git a/core/modules/user/user.module b/core/modules/user/user.module
index 5d39ce3..323da0c 100644
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -232,15 +232,6 @@ function user_load_multiple(array $uids = NULL, $reset = FALSE) {
 /**
  * Loads a user object.
  *
- * Drupal has a global $user object, which represents the currently-logged-in
- * user. So to avoid confusion and to avoid clobbering the global $user object,
- * it is a good idea to assign the result of this function to a different local
- * variable, generally $account. If you actually do want to act as the user you
- * are loading, it is essential to call drupal_save_session(FALSE); first.
- * See
- * @link http://drupal.org/node/218104 Safely impersonating another user @endlink
- * for more information.
- *
  * @param int $uid
  *   Integer specifying the user ID to load.
  * @param bool $reset
@@ -587,7 +578,7 @@ function user_menu_breadcrumb_alter(&$active_trail, $item) {
  * session, saves the login timestamp, calls hook_user_login(), and generates a
  * new session.
  *
- * The global $user object is replaced with the passed in account.
+ * The current user is replaced with the passed in account.
  *
  * @param \Drupal\user\UserInterface $account
  *   The account to log in.
@@ -595,8 +586,7 @@ function user_menu_breadcrumb_alter(&$active_trail, $item) {
  * @see hook_user_login()
  */
 function user_login_finalize(UserInterface $account) {
-  global $user;
-  $user = $account;
+  \Drupal::currentUser()->setAccount($account);
   \Drupal::logger('user')->notice('Session opened for %name.', array('%name' => $account->getUsername()));
   // Update the user table timestamp noting user has logged in.
   // This is also used to invalidate one-time login links.
@@ -796,7 +786,6 @@ function user_cancel($edit, $uid, $method) {
  * @see user_cancel()
  */
 function _user_cancel($edit, $account, $method) {
-  global $user;
   $logger = \Drupal::logger('user');
 
   switch ($method) {
@@ -829,8 +818,8 @@ function _user_cancel($edit, $account, $method) {
   // their session though, as we might have information in it, and we can't
   // regenerate it because batch API uses the session ID, we will regenerate it
   // in _user_cancel_session_regenerate().
-  if ($account->id() == $user->id()) {
-    $user = new AnonymousUserSession();
+  if ($account->id() == \Drupal::currentUser()->id()) {
+    \Drupal::currentUser()->setAccount(new AnonymousUserSession());
   }
 }