Testing a Single Page Application while simulating the backend

I have a single page application developed using javascript, react and redux that communicates with the backend via web socket, rest and json.

I wish to explore the possibility of working independently of the backend, both as I develop and in terms of treating the front end as a subsystem and performing subsystem tests on it.

Is this a good approach? What tools would you recommend? For example, I have used selenium previously with python. Would it be a sensible option for me to write my own simple test environment using a selenium api where tests are configured in their setup to respond to rest requests from the front end in the appropriate manner. Maybe there are better approaches.