diff --git a/app/Http/Controllers/API/v1/AuthController.php b/app/Http/Controllers/API/v1/AuthController.php
index 1d537c976..0b68437e9 100644
--- a/app/Http/Controllers/API/v1/AuthController.php
+++ b/app/Http/Controllers/API/v1/AuthController.php
@@ -4,167 +4,30 @@
 
 use App\Http\Controllers\Backend\Auth\LoginController;
 use App\Http\Resources\UserSettingsResource;
-use App\Models\User;
+use App\Providers\AuthServiceProvider;
 use Illuminate\Http\JsonResponse;
 use Illuminate\Http\Request;
-use Illuminate\Support\Facades\Hash;
-use Illuminate\Support\Facades\Validator;
-use App\Providers\AuthServiceProvider;
-use Illuminate\Validation\ValidationException;
 
 class AuthController extends Controller
 {
-    /**
-     * @OA\Post(
-     *      path="/auth/signup",
-     *      operationId="registerUser",
-     *      tags={"Auth"},
-     *      summary="register new user",
-     *      @OA\RequestBody(
-     *          required=true,
-     *          @OA\JsonContent(
-     *              @OA\Property(
-     *                  property="username",
-     *                  type="string",
-     *                  minLength=3,
-     *                  maxLength=25,
-     *                  pattern="^[a-zA-Z0-9_]*$",
-     *                  description="Username",
-     *                  example="Gertrud123"
-     *              ),
-     *              @OA\Property (
-     *                  property="name",
-     *                  type="string",
-     *                  maxLength=50,
-     *              ),
-     *              @OA\Property (
-     *                  property="email",
-     *                  example="mail@example.com"
-     *              ),
-     *              @OA\Property(
-     *                  property="password",
-     *                  description="password",
-     *                  type="string",
-     *                  minLength=8,
-     *                  maxLength=255,
-     *                  example="thisisnotasecurepassword123"
-     *              ),
-     *              @OA\Property (
-     *                  property="password_confirmation",
-     *                  description="confirmation of the password-field.",
-     *                  type="string",
-     *                  minLength=8,
-     *                  maxLength=255,
-     *                  example="thisisnotasecurepassword123"
-     *              )
-     *          )
-     *      ),
-     *      @OA\Response(
-     *          response=200,
-     *          description="successful operation",
-     *          @OA\JsonContent(
-     *              @OA\Property(property="data", type="object",
-     *                      ref="#/components/schemas/BearerTokenResponse"
-     *              )
-     *          )
-     *       ),
-     *       @OA\Response(response=401, description="Other (not specified) error occured"),
-     *       @OA\Response(response=422, description="Username or email is already taken, or other input error")
-     *     )
-     *
-     *
-     * @param Request $request
-     *
-     * @return JsonResponse
-     * @throws ValidationException
-     * @api v1
-     */
-    public function register(Request $request): JsonResponse {
-        $validator = Validator::make($request->all(), [
-            'username' => ['required', 'unique:users', 'min:3', 'max:25', 'regex:/^[a-zA-Z0-9_]*$/'],
-            'name'     => ['required', 'max:50'],
-            'email'    => ['required', 'email', 'unique:users', 'max:255'],
-            'password' => ['required', 'confirmed', 'max:255'],
-        ]);
-
-        if ($validator->fails()) {
-            return response()->json([
-                                        'status' => 'error',
-                                        'errors' => $validator->errors()
-                                    ], 422);
-        }
-
-        $validated               = $validator->validated();
-        $validated['password']   = Hash::make($validated['password']);
-        $validated['last_login'] = now();
-        $user                    = User::create($validated);
-
-        if ($user->wasRecentlyCreated) {
-            $userToken = $user->createToken('token', array_keys(AuthServiceProvider::$scopes));
-            return $this->sendResponse(
-                data: [
-                          'token'      => $userToken->accessToken,
-                          'expires_at' => $userToken->token->expires_at->toIso8601String()
-                      ],
-                code: 201
-            );
-        }
-        return $this->sendError("Sorry! Registration is not successful.", 401);
-    }
 
     /**
-     * @OA\Post(
-     *      path="/auth/login",
-     *      operationId="loginUser",
-     *      tags={"Auth"},
-     *      summary="Login with username & password",
-     *      @OA\RequestBody(
-     *          required=true,
-     *          @OA\JsonContent(
-     *              @OA\Property(
-     *                  property="login",
-     *                  type="string",
-     *                  minLength=8,
-     *                  maxLength=255,
-     *                  description="Username or email",
-     *                  example="gertrud@traewelling.de"
-     *              ),
-     *              @OA\Property(
-     *                  property="password",
-     *                  description="password",
-     *                  type="string",
-     *                  minLength=8,
-     *                  maxLength=255,
-     *                  example="thisisnotasecurepassword123"
-     *              )
-     *          )
-     *      ),
-     *      @OA\Response(
-     *          response=200,
-     *          description="successful operation",
-     *          @OA\JsonContent(
-     *              @OA\Property(property="data", type="object",
-     *                      ref="#/components/schemas/BearerTokenResponse"
-     *              )
-     *          )
-     *       ),
-     *       @OA\Response(response=400, description="Bad request"),
-     *       @OA\Response(response=401, description="Non-matching credentials")
-     *     )
-     *
-     *
      * @param Request $request
      *
      * @return JsonResponse
-     * @api v1
+     * @deprecated Remove before 2023-10! Maybe earlier - if possible. Deprecation is already announced since
+     *             November'22.
      */
     public function login(Request $request): JsonResponse {
         $validated = $request->validate(['login' => ['required', 'max:255'], 'password' => ['required', 'min:8', 'max:255']]);
 
         if (LoginController::login($validated['login'], $validated['password'])) {
             $token = $request->user()->createToken('token', array_keys(AuthServiceProvider::$scopes));
-            return $this->sendResponse(['token'      => $token->accessToken,
-                                        'expires_at' => $token->token->expires_at->toIso8601String()])
+            return $this->sendResponse([
+                                           'WARNING'    => 'This endpoint (login) is deprecated and will be removed in the following weeks. Please migrate to use OAuth2. More information: https://github.com/Traewelling/traewelling/issues/1772',
+                                           'token'      => $token->accessToken,
+                                           'expires_at' => $token->token->expires_at->toIso8601String(),
+                                       ])
                         ->header('Authorization', $token->accessToken);
         }
         return $this->sendError('Non-matching credentials', 401);
diff --git a/routes/api.php b/routes/api.php
index 1c28f0ee7..21aac4054 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -33,8 +33,7 @@
 Route::group(['prefix' => 'v1', 'middleware' => ['return-json']], static function() {
     Route::group(['prefix' => 'auth'], function() {
         Route::post('login', [v1Auth::class, 'login']);
-        Route::post('signup', [v1Auth::class, 'register']);
-        Route::group(['middleware' => 'auth:api'], function() {
+        Route::group(['middleware' => 'auth:api'], static function() {
             Route::post('refresh', [v1Auth::class, 'refresh']);
             Route::post('logout', [v1Auth::class, 'logout']);
             Route::get('user', [v1Auth::class, 'user']);