ReactのRouterがうまく機能しない

Question

ReactでSPIの作成をしようと考えています。
ですが、npm start で画面を表示しても、Home.jsx が表示されません。
エラーメッセージや警告なども表示されていないため、どこを修正すれば良いのかがわかりません。
知識のある方お教えいただければ幸いです。。

import {
    createStore as reduxCreateStore,
    combineReducers,
    applyMiddleware
} from 'redux';
import { connectRouter, routerMiddleware } from 'connected-react-router';
import { ProductReducer } from '../product/reducers';
import thunk from 'redux-thunk';

export default function cretateStore(history) {
    return reduxCreateStore(
        combineReducers({
            router: connectRouter(history),
            products: ProductReducer
        }),
        applyMiddleware(
            routerMiddleware(history),
            thunk
        )
    );
}

import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import createStore from './redux/store/store';
import { ConnectedRouter } from 'connected-react-router';
import * as History from 'history'; 
import './index.css';
import App from './App';
import * as serviceWorker from './serviceWorker';

const history = History.createBrowserHistory();
export const store = createStore(history);

ReactDOM.render(
  <Provider store={store}>
    <ConnectedRouter history={history}>
      <App />
    </ConnectedRouter>
  </Provider>,
  document.getElementById('root')
);

// If you want your app to work offline and load faster, you can change
// unregister() to register() below. Note this comes with some pitfalls.
// Learn more about service workers: https://bit.ly/CRA-PWA
serviceWorker.unregister();

import React from 'react';
import { Switch, Route } from 'react-router';
import { Home, About } from './templates';

const Router = () => {
    return(
        <Switch>
            <Route exact path={"(/)?"} component={Home} />
            <Route exact path={"/about"} component={About} />
        </Switch>
    );
};

export default Router;

import React from "react";
import Router from './Router';

const App = () => {
  return(
    <main>
      <Router />
    </main>
  )
}

export default App;