diff --git a/blechreiz/calendarCredentials.dat b/blechreiz/calendarCredentials.dat
new file mode 100644
index 0000000..95dd964
Binary files /dev/null and b/blechreiz/calendarCredentials.dat differ
diff --git a/eventplanner_gcal/google_sync.py b/eventplanner_gcal/google_sync.py
index 6501f63..e582b1f 100644
--- a/eventplanner_gcal/google_sync.py
+++ b/eventplanner_gcal/google_sync.py
@@ -308,9 +308,7 @@ def delete_all_gcal_events(service=None):
         return 0
 
     # Use batch request for efficiency
-    from googleapiclient.http import BatchHttpRequest
-
-    batch = BatchHttpRequest()
+    batch = service.new_batch_http_request()
     for gcal_id in gcal_ids:
         batch.add(service.events().delete(calendarId="primary", eventId=gcal_id))
 
@@ -359,9 +357,7 @@ def sync_from_local_to_google(service=None):
     events_to_create_django_id = local_events_django_id - events_at_google_django_id
     events_to_delete_google_id = events_at_google_google_id - local_events_google_id
 
-    from googleapiclient.http import BatchHttpRequest
-
-    batch = BatchHttpRequest()
+    batch = service.new_batch_http_request()
     batch_is_empty = True
 
     for event_django_id in events_to_create_django_id:
diff --git a/eventplanner_gcal/management/commands/gcal_setup.py b/eventplanner_gcal/management/commands/gcal_setup.py
new file mode 100644
index 0000000..bb5e22b
--- /dev/null
+++ b/eventplanner_gcal/management/commands/gcal_setup.py
@@ -0,0 +1,80 @@
+"""
+One-time OAuth2 setup command for Google Calendar integration.
+
+Run this locally (not in Docker) to authorize the app and generate
+the credentials token file (calendarCredentials.dat).
+
+Usage:
+    python manage.py gcal_setup --client-secrets /path/to/client_secret_*.json
+
+The command opens a browser for the OAuth2 consent flow, then saves
+the access+refresh token to the path configured in settings.GCAL_COUPLING['credentials_file'].
+Copy that file to the server afterwards.
+"""
+
+import os
+import pickle
+
+from django.conf import settings
+from django.core.management.base import BaseCommand, CommandError
+
+SCOPES = ["https://www.googleapis.com/auth/calendar"]
+
+
+class Command(BaseCommand):
+    help = (
+        "Perform one-time OAuth2 authorization for Google Calendar. "
+        "Run locally, then copy the resulting credentials file to the server."
+    )
+
+    def add_arguments(self, parser):
+        parser.add_argument(
+            "--client-secrets",
+            required=True,
+            metavar="FILE",
+            help="Path to the client_secret_*.json downloaded from Google Cloud Console",
+        )
+
+    def handle(self, *args, **options):
+        try:
+            from google_auth_oauthlib.flow import InstalledAppFlow
+        except ImportError:
+            raise CommandError(
+                "google-auth-oauthlib is not installed. "
+                "Run: pip install google-auth-oauthlib"
+            )
+
+        client_secrets = options["client_secrets"]
+        if not os.path.exists(client_secrets):
+            raise CommandError(f"Client secrets file not found: {client_secrets}")
+
+        credentials_file = settings.GCAL_COUPLING["credentials_file"]
+
+        self.stdout.write(
+            "Starting OAuth2 flow. A browser window will open for authorization."
+        )
+        self.stdout.write(
+            "Make sure you are authorizing with the Google account whose "
+            "calendar you want to use.\n"
+        )
+
+        flow = InstalledAppFlow.from_client_secrets_file(client_secrets, SCOPES)
+        creds = flow.run_local_server(port=0)
+
+        os.makedirs(os.path.dirname(credentials_file), exist_ok=True) if os.path.dirname(credentials_file) else None
+
+        with open(credentials_file, "wb") as token:
+            pickle.dump(creds, token)
+
+        self.stdout.write(
+            self.style.SUCCESS(
+                f"Credentials saved to: {credentials_file}\n"
+                f"Copy this file to the server at the same path inside the container."
+            )
+        )
+        self.stdout.write(
+            "\nTo copy to server (adjust paths as needed):\n"
+            f"  docker cp {credentials_file} blechreiz:/app/calendarCredentials.dat\n"
+            "Or via scp:\n"
+            f"  scp {credentials_file} core@server.fritz.box:/docker/blechreiz-website/calendarCredentials.dat"
+        )