diff --git a/wagtail/contrib/settings/tests/test_admin.py b/wagtail/contrib/settings/tests/test_admin.py
index 234d51024..5f22025ee 100644
--- a/wagtail/contrib/settings/tests/test_admin.py
+++ b/wagtail/contrib/settings/tests/test_admin.py
@@ -21,7 +21,7 @@ class TestSettingMenu(TestCase, WagtailTestUtils):
             username='test', email='test@email.com', password='password')
         user.user_permissions.add(Permission.objects.get_by_natural_key(
             codename='access_admin', app_label='wagtailadmin', model='admin'))
-        self.client.login(username='test', password='password')
+        self.assertTrue(self.client.login(username='test', password='password'))
         return user
 
     def test_menu_item_in_admin(self):
diff --git a/wagtail/tests/utils.py b/wagtail/tests/utils.py
index 8374c624b..3bf1427cb 100644
--- a/wagtail/tests/utils.py
+++ b/wagtail/tests/utils.py
@@ -35,7 +35,9 @@ class WagtailTestUtils(object):
 
         user_model = get_user_model()
         # Login
-        self.client.login(password='password', **{user_model.USERNAME_FIELD: 'test@email.com'})
+        self.assertTrue(
+            self.client.login(password='password', **{user_model.USERNAME_FIELD: 'test@email.com'})
+        )
 
         return user
 
diff --git a/wagtail/wagtailadmin/tests/test_account_management.py b/wagtail/wagtailadmin/tests/test_account_management.py
index 9c0faf98b..6836cda11 100644
--- a/wagtail/wagtailadmin/tests/test_account_management.py
+++ b/wagtail/wagtailadmin/tests/test_account_management.py
@@ -76,8 +76,8 @@ class TestAuthentication(TestCase, WagtailTestUtils):
         This tests issue #431
         """
         # Login as unprivileged user
-        get_user_model().objects.create(username='unprivileged', password='123')
-        self.client.login(username='unprivileged', password='123')
+        get_user_model().objects.create_user(username='unprivileged', password='123')
+        self.assertTrue(self.client.login(username='unprivileged', password='123'))
 
         # Get login page
         response = self.client.get(reverse('wagtailadmin_login'))
@@ -268,7 +268,7 @@ class TestAccountManagementForNonModerator(TestCase, WagtailTestUtils):
         self.submitter = get_user_model().objects.create_user('submitter', 'submitter@example.com', 'password')
         self.submitter.groups.add(Group.objects.get(name='Editors'))
 
-        self.client.login(username=self.submitter.username, password='password')
+        self.assertTrue(self.client.login(username=self.submitter.username, password='password'))
 
     def test_notification_preferences_form_is_reduced_for_non_moderators(self):
         """
@@ -297,7 +297,7 @@ class TestAccountManagementForAdminOnlyUser(TestCase, WagtailTestUtils):
         )
         self.admin_only_user.groups.add(admin_only_group)
 
-        self.client.login(username=self.admin_only_user.username, password='password')
+        self.assertTrue(self.client.login(username=self.admin_only_user.username, password='password'))
 
     def test_notification_preferences_view_redirects_for_admin_only_users(self):
         """
diff --git a/wagtail/wagtailadmin/tests/test_pages_views.py b/wagtail/wagtailadmin/tests/test_pages_views.py
index 68bcc091f..7b241e9f9 100644
--- a/wagtail/wagtailadmin/tests/test_pages_views.py
+++ b/wagtail/wagtailadmin/tests/test_pages_views.py
@@ -226,7 +226,7 @@ class TestPageExplorerSignposting(TestCase, WagtailTestUtils):
         self.root_page.add_child(instance=self.no_site_page)
 
     def test_admin_at_root(self):
-        self.client.login(username='superuser', password='password')
+        self.assertTrue(self.client.login(username='superuser', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore_root'))
         self.assertEqual(response.status_code, 200)
         # Administrator (or user with add_site permission) should get the full message
@@ -241,7 +241,7 @@ class TestPageExplorerSignposting(TestCase, WagtailTestUtils):
         self.assertContains(response, """<a href="/admin/sites/">Configure a site now.</a>""")
 
     def test_admin_at_non_site_page(self):
-        self.client.login(username='superuser', password='password')
+        self.assertTrue(self.client.login(username='superuser', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore', args=(self.no_site_page.id, )))
         self.assertEqual(response.status_code, 200)
         # Administrator (or user with add_site permission) should get a warning about
@@ -256,14 +256,14 @@ class TestPageExplorerSignposting(TestCase, WagtailTestUtils):
         self.assertContains(response, """<a href="/admin/sites/">Configure a site now.</a>""")
 
     def test_admin_at_site_page(self):
-        self.client.login(username='superuser', password='password')
+        self.assertTrue(self.client.login(username='superuser', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore', args=(self.site_page.id, )))
         self.assertEqual(response.status_code, 200)
         # There should be no warning message here
         self.assertNotContains(response, "Pages created here will not be accessible")
 
     def test_nonadmin_at_root(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore_root'))
         self.assertEqual(response.status_code, 200)
         # Non-admin should get a simple "create pages as children of the homepage" prompt
@@ -274,7 +274,7 @@ class TestPageExplorerSignposting(TestCase, WagtailTestUtils):
         )
 
     def test_nonadmin_at_non_site_page(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore', args=(self.no_site_page.id, )))
         self.assertEqual(response.status_code, 200)
         # Non-admin should get a warning about unroutable pages
@@ -287,7 +287,7 @@ class TestPageExplorerSignposting(TestCase, WagtailTestUtils):
         )
 
     def test_nonadmin_at_site_page(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         response = self.client.get(reverse('wagtailadmin_explore', args=(self.site_page.id, )))
         self.assertEqual(response.status_code, 200)
         # There should be no warning message here
diff --git a/wagtail/wagtailadmin/tests/tests.py b/wagtail/wagtailadmin/tests/tests.py
index 35e21f533..bc999e963 100644
--- a/wagtail/wagtailadmin/tests/tests.py
+++ b/wagtail/wagtailadmin/tests/tests.py
@@ -64,7 +64,7 @@ class TestHome(TestCase, WagtailTestUtils):
         # cause a failure when generating Gravatar URLs
         get_user_model().objects.create_superuser(username='snowman', email='☃@thenorthpole.com', password='password')
         # Login
-        self.client.login(username='snowman', password='password')
+        self.assertTrue(self.client.login(username='snowman', password='password'))
         response = self.client.get(reverse('wagtailadmin_home'))
         self.assertEqual(response.status_code, 200)
 
@@ -253,7 +253,7 @@ class TestUserPassesTestPermissionDecorator(TestCase):
     def test_user_passes_test(self):
         # create and log in as a user called Bob
         get_user_model().objects.create_superuser(first_name='Bob', last_name='Mortimer', username='test', email='test@email.com', password='password')
-        self.client.login(username='test', password='password')
+        self.assertTrue(self.client.login(username='test', password='password'))
 
         response = self.client.get(reverse('testapp_bob_only_zone'))
         self.assertEqual(response.status_code, 200)
@@ -261,7 +261,7 @@ class TestUserPassesTestPermissionDecorator(TestCase):
     def test_user_fails_test(self):
         # create and log in as a user not called Bob
         get_user_model().objects.create_superuser(first_name='Vic', last_name='Reeves', username='test', email='test@email.com', password='password')
-        self.client.login(username='test', password='password')
+        self.assertTrue(self.client.login(username='test', password='password'))
 
         response = self.client.get(reverse('testapp_bob_only_zone'))
         self.assertRedirects(response, reverse('wagtailadmin_home'))
diff --git a/wagtail/wagtaildocs/tests.py b/wagtail/wagtaildocs/tests.py
index 65db7808f..b86fb6132 100644
--- a/wagtail/wagtaildocs/tests.py
+++ b/wagtail/wagtaildocs/tests.py
@@ -1148,7 +1148,7 @@ class TestEditOnlyPermissions(TestCase, WagtailTestUtils):
         user.groups.add(self.changers_group)
 
         user.user_permissions.add(admin_permission)
-        self.client.login(username='changeonly', password='password')
+        self.assertTrue(self.client.login(username='changeonly', password='password'))
 
     def test_get_index(self):
         response = self.client.get(reverse('wagtaildocs:index'))
diff --git a/wagtail/wagtailforms/tests.py b/wagtail/wagtailforms/tests.py
index b07dc41e1..2dc8be280 100644
--- a/wagtail/wagtailforms/tests.py
+++ b/wagtail/wagtailforms/tests.py
@@ -184,7 +184,7 @@ class TestFormsIndex(TestCase):
     fixtures = ['test.json']
 
     def setUp(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         self.form_page = Page.objects.get(url_path='/home/contact-us/')
 
     def make_form_pages(self):
@@ -250,7 +250,7 @@ class TestFormsIndex(TestCase):
 
     def test_cannot_see_forms_without_permission(self):
         # Login with as a user without permission to see forms
-        self.client.login(username='eventeditor', password='password')
+        self.assertTrue(self.client.login(username='eventeditor', password='password'))
 
         response = self.client.get(reverse('wagtailforms:index'))
 
@@ -399,7 +399,7 @@ class TestDeleteFormSubmission(TestCase):
     fixtures = ['test.json']
 
     def setUp(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         self.form_page = Page.objects.get(url_path='/home/contact-us/')
 
     def test_delete_submission_show_cofirmation(self):
@@ -425,7 +425,7 @@ class TestDeleteFormSubmission(TestCase):
         self.assertRedirects(response, reverse("wagtailforms:list_submissions", args=(self.form_page.id, )))
 
     def test_delete_submission_bad_permissions(self):
-        self.client.login(username="eventeditor", password="password")
+        self.assertTrue(self.client.login(username="eventeditor", password="password"))
 
         response = self.client.post(reverse(
             'wagtailforms:delete_submission',
@@ -443,7 +443,7 @@ class TestIssue798(TestCase):
     fixtures = ['test.json']
 
     def setUp(self):
-        self.client.login(username='siteeditor', password='password')
+        self.assertTrue(self.client.login(username='siteeditor', password='password'))
         self.form_page = Page.objects.get(url_path='/home/contact-us/').specific
 
         # Add a number field to the page
diff --git a/wagtail/wagtailimages/tests/test_admin_views.py b/wagtail/wagtailimages/tests/test_admin_views.py
index 399004756..08f05a56e 100644
--- a/wagtail/wagtailimages/tests/test_admin_views.py
+++ b/wagtail/wagtailimages/tests/test_admin_views.py
@@ -915,7 +915,7 @@ class TestEditOnlyPermissions(TestCase, WagtailTestUtils):
         )
 
         user.groups.add(image_changers_group)
-        self.client.login(username='changeonly', password='password')
+        self.assertTrue(self.client.login(username='changeonly', password='password'))
 
     def test_get_index(self):
         response = self.client.get(reverse('wagtailimages:index'))
diff --git a/wagtail/wagtailsites/tests.py b/wagtail/wagtailsites/tests.py
index 3d9f15fbe..8c2f054b3 100644
--- a/wagtail/wagtailsites/tests.py
+++ b/wagtail/wagtailsites/tests.py
@@ -266,7 +266,7 @@ class TestLimitedPermissions(TestCase, WagtailTestUtils):
         )
 
         # Login
-        self.client.login(username='test', password='password')
+        self.assertTrue(self.client.login(username='test', password='password'))
 
         self.home_page = Page.objects.get(id=2)
         self.localhost = Site.objects.all()[0]
diff --git a/wagtail/wagtailsnippets/tests.py b/wagtail/wagtailsnippets/tests.py
index 677d92683..353001dfa 100644
--- a/wagtail/wagtailsnippets/tests.py
+++ b/wagtail/wagtailsnippets/tests.py
@@ -518,7 +518,7 @@ class TestAddOnlyPermissions(TestCase, WagtailTestUtils):
         add_permission = Permission.objects.get(content_type__app_label='tests', codename='add_advert')
         admin_permission = Permission.objects.get(content_type__app_label='wagtailadmin', codename='access_admin')
         user.user_permissions.add(add_permission, admin_permission)
-        self.client.login(username='addonly', password='password')
+        self.assertTrue(self.client.login(username='addonly', password='password'))
 
     def test_get_index(self):
         response = self.client.get(reverse('wagtailsnippets:list',
@@ -562,7 +562,7 @@ class TestEditOnlyPermissions(TestCase, WagtailTestUtils):
         change_permission = Permission.objects.get(content_type__app_label='tests', codename='change_advert')
         admin_permission = Permission.objects.get(content_type__app_label='wagtailadmin', codename='access_admin')
         user.user_permissions.add(change_permission, admin_permission)
-        self.client.login(username='changeonly', password='password')
+        self.assertTrue(self.client.login(username='changeonly', password='password'))
 
     def test_get_index(self):
         response = self.client.get(reverse('wagtailsnippets:list',
@@ -606,7 +606,7 @@ class TestDeleteOnlyPermissions(TestCase, WagtailTestUtils):
         change_permission = Permission.objects.get(content_type__app_label='tests', codename='delete_advert')
         admin_permission = Permission.objects.get(content_type__app_label='wagtailadmin', codename='access_admin')
         user.user_permissions.add(change_permission, admin_permission)
-        self.client.login(username='deleteonly', password='password')
+        self.assertTrue(self.client.login(username='deleteonly', password='password'))
 
     def test_get_index(self):
         response = self.client.get(reverse('wagtailsnippets:list',