diff --git a/fastapi_users/authentication/__init__.py b/fastapi_users/authentication/__init__.py
index d2aa3529..25a5a23f 100644
--- a/fastapi_users/authentication/__init__.py
+++ b/fastapi_users/authentication/__init__.py
@@ -9,7 +9,7 @@ from fastapi_users import models
 from fastapi_users.authentication.base import BaseAuthentication  # noqa: F401
 from fastapi_users.authentication.cookie import CookieAuthentication  # noqa: F401
 from fastapi_users.authentication.jwt import JWTAuthentication  # noqa: F401
-from fastapi_users.manager import UserManager, UserManagerDependency
+from fastapi_users.manager import BaseUserManager, UserManagerDependency
 
 INVALID_CHARS_PATTERN = re.compile(r"[^0-9a-zA-Z_]")
 INVALID_LEADING_CHARS_PATTERN = re.compile(r"^[^a-zA-Z_]+")
@@ -108,7 +108,7 @@ class Authenticator:
     async def _authenticate(
         self,
         *args,
-        user_manager: UserManager[models.UC, models.UD],
+        user_manager: BaseUserManager[models.UC, models.UD],
         optional: bool = False,
         active: bool = False,
         verified: bool = False,
diff --git a/fastapi_users/authentication/base.py b/fastapi_users/authentication/base.py
index a8b9fe4a..91d3c5db 100644
--- a/fastapi_users/authentication/base.py
+++ b/fastapi_users/authentication/base.py
@@ -4,7 +4,7 @@ from fastapi import Response
 from fastapi.security.base import SecurityBase
 
 from fastapi_users import models
-from fastapi_users.manager import UserManager
+from fastapi_users.manager import BaseUserManager
 
 T = TypeVar("T")
 
@@ -28,7 +28,9 @@ class BaseAuthentication(Generic[T, models.UC, models.UD]):
         self.logout = logout
 
     async def __call__(
-        self, credentials: Optional[T], user_manager: UserManager[models.UC, models.UD]
+        self,
+        credentials: Optional[T],
+        user_manager: BaseUserManager[models.UC, models.UD],
     ) -> Optional[models.UD]:
         raise NotImplementedError()
 
diff --git a/fastapi_users/authentication/cookie.py b/fastapi_users/authentication/cookie.py
index baf8fb81..d8188f1e 100644
--- a/fastapi_users/authentication/cookie.py
+++ b/fastapi_users/authentication/cookie.py
@@ -8,7 +8,7 @@ from pydantic import UUID4
 from fastapi_users import models
 from fastapi_users.authentication import BaseAuthentication
 from fastapi_users.jwt import SecretType, decode_jwt, generate_jwt
-from fastapi_users.manager import UserManager, UserNotExists
+from fastapi_users.manager import BaseUserManager, UserNotExists
 
 
 class CookieAuthentication(
@@ -69,7 +69,7 @@ class CookieAuthentication(
     async def __call__(
         self,
         credentials: Optional[str],
-        user_manager: UserManager[models.UC, models.UD],
+        user_manager: BaseUserManager[models.UC, models.UD],
     ) -> Optional[models.UD]:
         if credentials is None:
             return None
diff --git a/fastapi_users/authentication/jwt.py b/fastapi_users/authentication/jwt.py
index c0020a84..8b13704a 100644
--- a/fastapi_users/authentication/jwt.py
+++ b/fastapi_users/authentication/jwt.py
@@ -8,7 +8,7 @@ from pydantic import UUID4
 from fastapi_users import models
 from fastapi_users.authentication.base import BaseAuthentication
 from fastapi_users.jwt import SecretType, decode_jwt, generate_jwt
-from fastapi_users.manager import UserManager, UserNotExists
+from fastapi_users.manager import BaseUserManager, UserNotExists
 
 
 class JWTAuthentication(
@@ -46,7 +46,7 @@ class JWTAuthentication(
     async def __call__(
         self,
         credentials: Optional[str],
-        user_manager: UserManager[models.UC, models.UD],
+        user_manager: BaseUserManager[models.UC, models.UD],
     ) -> Optional[models.UD]:
         if credentials is None:
             return None
diff --git a/fastapi_users/fastapi_users.py b/fastapi_users/fastapi_users.py
index 44384a4d..322b7944 100644
--- a/fastapi_users/fastapi_users.py
+++ b/fastapi_users/fastapi_users.py
@@ -1,13 +1,11 @@
 from typing import Any, Callable, Dict, Generic, Optional, Sequence, Type
 
-from fastapi import APIRouter, Depends, Request
+from fastapi import APIRouter, Request
 
 from fastapi_users import models
 from fastapi_users.authentication import Authenticator, BaseAuthentication
-from fastapi_users.db import BaseUserDatabase
-from fastapi_users.db.base import UserDatabaseDependency
 from fastapi_users.jwt import SecretType
-from fastapi_users.manager import UserManager, ValidatePasswordProtocol
+from fastapi_users.manager import UserManagerDependency
 from fastapi_users.router import (
     get_auth_router,
     get_register_router,
@@ -28,21 +26,19 @@ class FastAPIUsers(Generic[models.U, models.UC, models.UU, models.UD]):
     """
     Main object that ties together the component for users authentication.
 
-    :param get_db: Dependency callable returning a database adapter instance.
+    :param get_user_manager: Dependency callable getter to inject the
+    user manager class instance.
     :param auth_backends: List of authentication backends.
     :param user_model: Pydantic model of a user.
     :param user_create_model: Pydantic model for creating a user.
     :param user_update_model: Pydantic model for updating a user.
     :param user_db_model: Pydantic model of a DB representation of a user.
 
-    :attribute get_user_manager: Dependency callable getter to inject the
-    user manager class instance.
     :attribute current_user: Dependency callable getter to inject authenticated user
     with a specific set of parameters.
     """
 
     authenticator: Authenticator
-    validate_password: Optional[ValidatePasswordProtocol]
     _user_model: Type[models.U]
     _user_create_model: Type[models.UC]
     _user_update_model: Type[models.UU]
@@ -50,18 +46,13 @@ class FastAPIUsers(Generic[models.U, models.UC, models.UU, models.UD]):
 
     def __init__(
         self,
-        get_db: UserDatabaseDependency[models.UD],
+        get_user_manager: UserManagerDependency[models.UC, models.UD],
         auth_backends: Sequence[BaseAuthentication],
         user_model: Type[models.U],
         user_create_model: Type[models.UC],
         user_update_model: Type[models.UU],
         user_db_model: Type[models.UD],
     ):
-        def get_user_manager(
-            user_db: BaseUserDatabase[models.UD] = Depends(get_db),
-        ):
-            return UserManager(user_db_model, user_db)
-
         self.authenticator = Authenticator(auth_backends, get_user_manager)
 
         self._user_model = user_model
diff --git a/fastapi_users/manager.py b/fastapi_users/manager.py
index 32088c83..0cde1105 100644
--- a/fastapi_users/manager.py
+++ b/fastapi_users/manager.py
@@ -1,12 +1,7 @@
-from typing import Any, Awaitable, Callable, Dict, Generic, Optional, Type, Union
+from typing import Any, Callable, Dict, Generic, Optional, Type, Union
 
 from pydantic.types import UUID4
 
-try:
-    from typing import Protocol
-except ImportError:  # pragma: no cover
-    from typing_extensions import Protocol  # type: ignore
-
 from fastapi.security import OAuth2PasswordRequestForm
 
 from fastapi_users import models, password
@@ -35,14 +30,7 @@ class InvalidPasswordException(FastAPIUsersException):
         self.reason = reason
 
 
-class ValidatePasswordProtocol(Protocol):  # pragma: no cover
-    def __call__(
-        self, password: str, user: Union[models.UC, models.UD]
-    ) -> Awaitable[None]:
-        pass
-
-
-class UserManager(Generic[models.UC, models.UD]):
+class BaseUserManager(Generic[models.UC, models.UD]):
 
     user_db_model: Type[models.UD]
     user_db: BaseUserDatabase[models.UD]
@@ -115,7 +103,7 @@ class UserManager(Generic[models.UC, models.UD]):
     async def validate_password(
         self, password: str, user: Union[models.UC, models.UD]
     ) -> None:
-        return
+        return  # pragma: no cover
 
     async def authenticate(
         self, credentials: OAuth2PasswordRequestForm
@@ -164,4 +152,4 @@ class UserManager(Generic[models.UC, models.UD]):
         return updated_user
 
 
-UserManagerDependency = Callable[..., UserManager[models.UC, models.UD]]
+UserManagerDependency = Callable[..., BaseUserManager[models.UC, models.UD]]
diff --git a/fastapi_users/router/auth.py b/fastapi_users/router/auth.py
index be3e28c2..7879ef0e 100644
--- a/fastapi_users/router/auth.py
+++ b/fastapi_users/router/auth.py
@@ -3,7 +3,7 @@ from fastapi.security import OAuth2PasswordRequestForm
 
 from fastapi_users import models
 from fastapi_users.authentication import Authenticator, BaseAuthentication
-from fastapi_users.manager import UserManager, UserManagerDependency
+from fastapi_users.manager import BaseUserManager, UserManagerDependency
 from fastapi_users.router.common import ErrorCode
 
 
@@ -23,7 +23,7 @@ def get_auth_router(
     async def login(
         response: Response,
         credentials: OAuth2PasswordRequestForm = Depends(),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         user = await user_manager.authenticate(credentials)
 
diff --git a/fastapi_users/router/oauth.py b/fastapi_users/router/oauth.py
index a9746ef3..ac60b460 100644
--- a/fastapi_users/router/oauth.py
+++ b/fastapi_users/router/oauth.py
@@ -8,7 +8,7 @@ from httpx_oauth.oauth2 import BaseOAuth2
 from fastapi_users import models
 from fastapi_users.authentication import Authenticator
 from fastapi_users.jwt import SecretType, decode_jwt, generate_jwt
-from fastapi_users.manager import UserManager, UserManagerDependency, UserNotExists
+from fastapi_users.manager import BaseUserManager, UserManagerDependency, UserNotExists
 from fastapi_users.password import generate_password, get_password_hash
 from fastapi_users.router.common import ErrorCode, run_handler
 
@@ -83,7 +83,7 @@ def get_oauth_router(
         request: Request,
         response: Response,
         access_token_state=Depends(oauth2_authorize_callback),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         token, state = access_token_state
         account_id, account_email = await oauth_client.get_id_email(
diff --git a/fastapi_users/router/register.py b/fastapi_users/router/register.py
index fd1db326..92b94e1c 100644
--- a/fastapi_users/router/register.py
+++ b/fastapi_users/router/register.py
@@ -6,7 +6,7 @@ from fastapi_users import models
 from fastapi_users.manager import (
     InvalidPasswordException,
     UserAlreadyExists,
-    UserManager,
+    BaseUserManager,
     UserManagerDependency,
 )
 from fastapi_users.router.common import ErrorCode, run_handler
@@ -27,7 +27,7 @@ def get_register_router(
     async def register(
         request: Request,
         user: user_create_model,  # type: ignore
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             created_user = await user_manager.create(user, safe=True)
diff --git a/fastapi_users/router/reset.py b/fastapi_users/router/reset.py
index 609d312f..a9a26358 100644
--- a/fastapi_users/router/reset.py
+++ b/fastapi_users/router/reset.py
@@ -8,7 +8,7 @@ from fastapi_users import models
 from fastapi_users.jwt import SecretType, decode_jwt, generate_jwt
 from fastapi_users.manager import (
     InvalidPasswordException,
-    UserManager,
+    BaseUserManager,
     UserManagerDependency,
     UserNotExists,
 )
@@ -32,7 +32,7 @@ def get_reset_password_router(
     async def forgot_password(
         request: Request,
         email: EmailStr = Body(..., embed=True),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             user = await user_manager.get_by_email(email)
@@ -56,7 +56,7 @@ def get_reset_password_router(
         request: Request,
         token: str = Body(...),
         password: str = Body(...),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             data = decode_jwt(
diff --git a/fastapi_users/router/users.py b/fastapi_users/router/users.py
index 2d62b75a..e368ff81 100644
--- a/fastapi_users/router/users.py
+++ b/fastapi_users/router/users.py
@@ -8,7 +8,7 @@ from fastapi_users.authentication import Authenticator
 from fastapi_users.manager import (
     InvalidPasswordException,
     UserAlreadyExists,
-    UserManager,
+    BaseUserManager,
     UserManagerDependency,
     UserNotExists,
 )
@@ -36,7 +36,7 @@ def get_users_router(
 
     async def get_user_or_404(
         id: UUID4,
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ) -> models.UD:
         try:
             return await user_manager.get(id)
@@ -58,7 +58,7 @@ def get_users_router(
         request: Request,
         user_update: user_update_model,  # type: ignore
         user: user_db_model = Depends(get_current_active_user),  # type: ignore
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             updated_user = await user_manager.update(user_update, user, safe=True)
@@ -101,7 +101,7 @@ def get_users_router(
         user_update: user_update_model,  # type: ignore
         request: Request,
         user=Depends(get_user_or_404),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             updated_user = await user_manager.update(user_update, user, safe=False)
@@ -135,7 +135,7 @@ def get_users_router(
     )
     async def delete_user(
         user=Depends(get_user_or_404),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         await user_manager.delete(user)
         return None
diff --git a/fastapi_users/router/verify.py b/fastapi_users/router/verify.py
index 3f7839e5..01b09653 100644
--- a/fastapi_users/router/verify.py
+++ b/fastapi_users/router/verify.py
@@ -8,7 +8,7 @@ from fastapi_users import models
 from fastapi_users.jwt import SecretType, decode_jwt, generate_jwt
 from fastapi_users.manager import (
     UserAlreadyVerified,
-    UserManager,
+    BaseUserManager,
     UserManagerDependency,
     UserNotExists,
 )
@@ -33,7 +33,7 @@ def get_verify_router(
     async def request_verify_token(
         request: Request,
         email: EmailStr = Body(..., embed=True),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             user = await user_manager.get_by_email(email)
@@ -60,7 +60,7 @@ def get_verify_router(
     async def verify(
         request: Request,
         token: str = Body(..., embed=True),
-        user_manager: UserManager[models.UC, models.UD] = Depends(get_user_manager),
+        user_manager: BaseUserManager[models.UC, models.UD] = Depends(get_user_manager),
     ):
         try:
             data = decode_jwt(
diff --git a/tests/conftest.py b/tests/conftest.py
index b9f87ed2..68280bbc 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -15,7 +15,7 @@ from fastapi_users.authentication import Authenticator, BaseAuthentication
 from fastapi_users.db import BaseUserDatabase
 from fastapi_users.jwt import SecretType
 from fastapi_users.manager import InvalidPasswordException
-from fastapi_users.manager import UserManager as BaseUserManager
+from fastapi_users.manager import BaseUserManager
 from fastapi_users.manager import UserNotExists
 from fastapi_users.models import BaseOAuthAccount, BaseOAuthAccountMixin
 from fastapi_users.password import get_password_hash
diff --git a/tests/test_authentication.py b/tests/test_authentication.py
index 6de2323b..93291cbf 100644
--- a/tests/test_authentication.py
+++ b/tests/test_authentication.py
@@ -6,7 +6,7 @@ from fastapi.security.base import SecurityBase
 
 from fastapi_users import models
 from fastapi_users.authentication import BaseAuthentication, DuplicateBackendNamesError
-from fastapi_users.manager import UserManager
+from fastapi_users.manager import BaseUserManager
 
 
 class MockSecurityScheme(SecurityBase):
@@ -24,7 +24,7 @@ class BackendNone(
     async def __call__(
         self,
         credentials: Optional[str],
-        user_manager: UserManager[models.UC, models.UD],
+        user_manager: BaseUserManager[models.UC, models.UD],
     ) -> Optional[models.UD]:
         return None
 
@@ -40,7 +40,7 @@ class BackendUser(
     async def __call__(
         self,
         credentials: Optional[str],
-        user_manager: UserManager[models.UC, models.UD],
+        user_manager: BaseUserManager[models.UC, models.UD],
     ) -> Optional[models.UD]:
         return self.user
 
diff --git a/tests/test_fastapi_users.py b/tests/test_fastapi_users.py
index 0edebf50..7a48c8a1 100644
--- a/tests/test_fastapi_users.py
+++ b/tests/test_fastapi_users.py
@@ -12,13 +12,13 @@ from tests.conftest import User, UserCreate, UserDB, UserUpdate
 @pytest.mark.asyncio
 async def test_app_client(
     secret,
-    get_mock_user_db,
+    get_user_manager,
     mock_authentication,
     oauth_client,
     get_test_client,
 ) -> AsyncGenerator[httpx.AsyncClient, None]:
     fastapi_users = FastAPIUsers[User, UserCreate, UserUpdate, UserDB](
-        get_mock_user_db,
+        get_user_manager,
         [mock_authentication],
         User,
         UserCreate,
diff --git a/tests/test_manager.py b/tests/test_manager.py
index dca5bc11..f8759a4e 100644
--- a/tests/test_manager.py
+++ b/tests/test_manager.py
@@ -4,13 +4,8 @@ import pytest
 from fastapi.security import OAuth2PasswordRequestForm
 from pytest_mock import MockerFixture
 
-from fastapi_users.manager import UserAlreadyExists, UserAlreadyVerified, UserManager
-from tests.conftest import UserCreate, UserDB
-
-
-@pytest.fixture
-def user_manager(mock_user_db) -> UserManager[UserCreate, UserDB]:
-    return UserManager(UserDB, mock_user_db)
+from fastapi_users.manager import UserAlreadyExists, UserAlreadyVerified
+from tests.conftest import UserCreate, UserDB, UserManager
 
 
 @pytest.fixture
@@ -28,25 +23,19 @@ class TestCreateUser:
     @pytest.mark.parametrize(
         "email", ["king.arthur@camelot.bt", "King.Arthur@camelot.bt"]
     )
-    async def test_existing_user(
-        self, email: str, user_manager: UserManager[UserCreate, UserDB]
-    ):
+    async def test_existing_user(self, email: str, user_manager: UserManager):
         user = UserCreate(email=email, password="guinevere")
         with pytest.raises(UserAlreadyExists):
             await user_manager.create(user)
 
     @pytest.mark.parametrize("email", ["lancelot@camelot.bt", "Lancelot@camelot.bt"])
-    async def test_regular_user(
-        self, email: str, user_manager: UserManager[UserCreate, UserDB]
-    ):
+    async def test_regular_user(self, email: str, user_manager: UserManager):
         user = UserCreate(email=email, password="guinevere")
         created_user = await user_manager.create(user)
         assert type(created_user) == UserDB
 
     @pytest.mark.parametrize("safe,result", [(True, False), (False, True)])
-    async def test_superuser(
-        self, user_manager: UserManager[UserCreate, UserDB], safe: bool, result: bool
-    ):
+    async def test_superuser(self, user_manager: UserManager, safe: bool, result: bool):
         user = UserCreate(
             email="lancelot@camelot.b", password="guinevere", is_superuser=True
         )
@@ -55,9 +44,7 @@ class TestCreateUser:
         assert created_user.is_superuser is result
 
     @pytest.mark.parametrize("safe,result", [(True, True), (False, False)])
-    async def test_is_active(
-        self, user_manager: UserManager[UserCreate, UserDB], safe: bool, result: bool
-    ):
+    async def test_is_active(self, user_manager: UserManager, safe: bool, result: bool):
         user = UserCreate(
             email="lancelot@camelot.b", password="guinevere", is_active=False
         )
@@ -69,14 +56,12 @@ class TestCreateUser:
 @pytest.mark.asyncio
 class TestVerifyUser:
     async def test_already_verified_user(
-        self, user_manager: UserManager[UserCreate, UserDB], verified_user: UserDB
+        self, user_manager: UserManager, verified_user: UserDB
     ):
         with pytest.raises(UserAlreadyVerified):
             await user_manager.verify(verified_user)
 
-    async def test_non_verified_user(
-        self, user_manager: UserManager[UserCreate, UserDB], user: UserDB
-    ):
+    async def test_non_verified_user(self, user_manager: UserManager, user: UserDB):
         user = await user_manager.verify(user)
         assert user.is_verified
 
@@ -89,7 +74,7 @@ class TestAuthenticate:
         create_oauth2_password_request_form: Callable[
             [str, str], OAuth2PasswordRequestForm
         ],
-        user_manager: UserManager[UserCreate, UserDB],
+        user_manager: UserManager,
     ):
         form = create_oauth2_password_request_form("lancelot@camelot.bt", "guinevere")
         user = await user_manager.authenticate(form)
@@ -101,7 +86,7 @@ class TestAuthenticate:
         create_oauth2_password_request_form: Callable[
             [str, str], OAuth2PasswordRequestForm
         ],
-        user_manager: UserManager[UserCreate, UserDB],
+        user_manager: UserManager,
     ):
         form = create_oauth2_password_request_form("king.arthur@camelot.bt", "percival")
         user = await user_manager.authenticate(form)
@@ -113,7 +98,7 @@ class TestAuthenticate:
         create_oauth2_password_request_form: Callable[
             [str, str], OAuth2PasswordRequestForm
         ],
-        user_manager: UserManager[UserCreate, UserDB],
+        user_manager: UserManager,
     ):
         form = create_oauth2_password_request_form(
             "king.arthur@camelot.bt", "guinevere"
@@ -129,7 +114,7 @@ class TestAuthenticate:
         create_oauth2_password_request_form: Callable[
             [str, str], OAuth2PasswordRequestForm
         ],
-        user_manager: UserManager[UserCreate, UserDB],
+        user_manager: UserManager,
     ):
         verify_and_update_password_patch = mocker.patch(
             "fastapi_users.password.verify_and_update_password"