diff --git a/tests/conftest.py b/tests/conftest.py
index 5399d8a..50f485d 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,4 +1,7 @@
 import os
+from unittest.mock import patch
+
+import pytest
 
 os.environ["SOCKETIO_ASYNC_MODE"] = "threading"
 os.environ["SECRET_KEY"] = "test-secret"
@@ -7,10 +10,16 @@
 os.environ["TESTING"] = "true"
 os.environ["LIMITER_STORAGE_URI"] = "memory://"
 
-import pytest
-
 
 @pytest.fixture(autouse=True, scope="session")
 def setup_test_env():
     # Already set at top level, but kept for clarity
     pass
+
+
+@pytest.fixture(autouse=True)
+def mock_redis():
+    """Globally mock Redis to avoid connection errors during tests."""
+    with patch("hookwise.tasks.redis_client") as mock_redis_client:
+        mock_redis_client.get.return_value = None
+        yield mock_redis_client
diff --git a/tests/test_replay.py b/tests/test_replay.py
new file mode 100644
index 0000000..350448a
--- /dev/null
+++ b/tests/test_replay.py
@@ -0,0 +1,119 @@
+import json
+from unittest.mock import ANY, patch
+
+import pytest
+from werkzeug.security import generate_password_hash
+
+from hookwise import create_app
+from hookwise.extensions import db
+from hookwise.models import User, WebhookConfig, WebhookLog
+
+
+@pytest.fixture
+def app():
+    app = create_app()
+    app.config["TESTING"] = True
+    app.config["WTF_CSRF_ENABLED"] = False
+    app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///:memory:"
+    return app
+
+
+@pytest.fixture
+def client(app):
+    with app.app_context():
+        db.create_all()
+        yield app.test_client()
+        db.session.remove()
+        db.drop_all()
+
+
+@pytest.fixture
+def auth_client(client, app):
+    with app.app_context():
+        user = User(username="testuser", password_hash=generate_password_hash("password"), role="admin")
+        db.session.add(user)
+        db.session.commit()
+        user_id = user.id
+        username = user.username
+        role = user.role
+
+    with client.session_transaction() as sess:
+        sess["user_id"] = user_id
+        sess["username"] = username
+        sess["role"] = role
+    return client
+
+
+@pytest.fixture
+def sample_config(app):
+    with app.app_context():
+        config = WebhookConfig(name="Test Config", bearer_token="token")
+        db.session.add(config)
+        db.session.commit()
+        return config.id
+
+
+@pytest.fixture
+def sample_log(app, sample_config):
+    with app.app_context():
+        log = WebhookLog(
+            config_id=sample_config,
+            request_id="req_1234567890",
+            payload=json.dumps({"key": "value"}),
+            status="processed",
+        )
+        db.session.add(log)
+        db.session.commit()
+        return log.id
+
+
+@patch("hookwise.api.redis_client")
+@patch("hookwise.tasks.redis_client")
+@patch("hookwise.api.process_webhook_task.delay")
+@patch("hookwise.api.log_to_web")
+def test_replay_webhook_success(mock_log_web, mock_delay, mock_redis1, mock_redis2, auth_client, sample_log):
+    response = auth_client.post(f"/history/replay/{sample_log}")
+
+    assert response.status_code == 200
+    assert response.json["status"] == "success"
+    assert response.json["message"] == "Replay queued"
+    assert "replay_" in response.json["request_id"]
+
+    mock_delay.assert_called_once_with(ANY, {"key": "value"}, response.json["request_id"])
+    mock_log_web.assert_called_once()
+
+
+@patch("hookwise.api.redis_client")
+@patch("hookwise.tasks.redis_client")
+def test_replay_webhook_not_found(mock_redis1, mock_redis2, auth_client):
+    response = auth_client.post("/history/replay/non-existent-id")
+    assert response.status_code == 404
+
+
+@patch("hookwise.api.redis_client")
+@patch("hookwise.tasks.redis_client")
+def test_replay_webhook_unauthorized(mock_redis1, mock_redis2, client, sample_log):
+    response = client.post(f"/history/replay/{sample_log}")
+    assert response.status_code == 302
+    assert "/login" in response.location
+
+
+@pytest.fixture
+def invalid_log(app, sample_config):
+    with app.app_context():
+        log = WebhookLog(
+            config_id=sample_config, request_id="req_invalid", payload="invalid json", status="processed"
+        )
+        db.session.add(log)
+        db.session.commit()
+        return log.id
+
+
+@patch("hookwise.api.redis_client")
+@patch("hookwise.tasks.redis_client")
+@patch("hookwise.api.process_webhook_task.delay")
+def test_replay_webhook_invalid_json(mock_delay, mock_redis1, mock_redis2, auth_client, invalid_log):
+    response = auth_client.post(f"/history/replay/{invalid_log}")
+    assert response.status_code == 500
+    assert response.json["status"] == "error"
+    mock_delay.assert_not_called()