diff --git a/zerver/lib/actions.py b/zerver/lib/actions.py
index dab3e964f1..eee28c6b46 100644
--- a/zerver/lib/actions.py
+++ b/zerver/lib/actions.py
@@ -4299,10 +4299,22 @@ def do_update_user_custom_profile_data(user_profile, data):
                              field_id=field['id'],
                              defaults={'value': field['value']})
 
+def do_send_create_user_group_event(user_group: UserGroup, members: List[UserProfile]) -> None:
+    event = dict(type="user_group",
+                 op="add",
+                 group=dict(name=user_group.name,
+                            members=[member.id for member in members],
+                            description=user_group.description,
+                            id=user_group.id,
+                            ),
+                 )
+    send_event(event, active_user_ids(user_group.realm_id))
+
 def check_add_user_group(realm, name, initial_members, description):
     # type: (Realm, Text, List[UserProfile], Text) -> None
     try:
-        create_user_group(name, initial_members, realm, description=description)
+        user_group = create_user_group(name, initial_members, realm, description=description)
+        do_send_create_user_group_event(user_group, initial_members)
     except django.db.utils.IntegrityError:
         raise JsonableError(_("User group '%s' already exists." % (name,)))
 
diff --git a/zerver/lib/events.py b/zerver/lib/events.py
index 40911306df..01f0631256 100644
--- a/zerver/lib/events.py
+++ b/zerver/lib/events.py
@@ -552,6 +552,10 @@ def apply_event(state, event, user_profile, client_gravatar, include_subscribers
     elif event['type'] == "update_global_notifications":
         assert event['notification_name'] in UserProfile.notification_setting_types
         state[event['notification_name']] = event['setting']
+    elif event['type'] == "user_group":
+        if event['op'] == 'add':
+            state['realm_user_groups'].append(event['group'])
+            state['realm_user_groups'].sort(key=lambda group: group['id'])
     else:
         raise AssertionError("Unexpected event type %s" % (event['type'],))
 
diff --git a/zerver/tests/test_events.py b/zerver/tests/test_events.py
index bd531dbae4..89f874d386 100644
--- a/zerver/tests/test_events.py
+++ b/zerver/tests/test_events.py
@@ -75,6 +75,7 @@ from zerver.lib.actions import (
     log_event,
     lookup_default_stream_groups,
     notify_realm_custom_profile_fields,
+    check_add_user_group,
 )
 from zerver.lib.events import (
     apply_events,
@@ -986,6 +987,24 @@ class EventsRegisterTest(ZulipTestCase):
         error = alert_words_checker('events[0]', events[0])
         self.assert_on_error(error)
 
+    def test_user_group_events(self) -> None:
+        user_group_add_checker = self.check_events_dict([
+            ('type', equals('user_group')),
+            ('op', equals('add')),
+            ('group', check_dict_only([
+                ('id', check_int),
+                ('name', check_string),
+                ('members', check_list(check_int)),
+                ('description', check_string),
+            ])),
+        ])
+        othello = self.example_user('othello')
+        zulip = get_realm('zulip')
+        events = self.do_test(lambda: check_add_user_group(zulip, 'backend', [othello],
+                                                           'Backend team'))
+        error = user_group_add_checker('events[0]', events[0])
+        self.assert_on_error(error)
+
     def test_default_stream_groups_events(self):
         # type: () -> None
         default_stream_groups_checker = self.check_events_dict([