connectedRouter Error: Could not find router reducer in state tree, it must be mounted under "router"

Question

For the sake of helping future souls with this issue, it turns out that according to the linked github discussions, that version 5.0 of the history package is causing the issue and downgrading to version 4.10.1 solves the problem for me.

npm install [email protected]

https://github.com/ReactTraining/history/issues/803

https://github.com/ReactTraining/history/issues/804

Add router in your reducer with using connectRouter and history

Refer this link

https://www.npmjs.com/package/connected-react-router

import { connectRouter } from 'connected-react-router'
const rootReducer = combineReducers({
  login: loginReducer,
  router: connectRouter(history),
});

The main issue is the version of the history package, with react-router-dom v5 you need to use history v4 (the latest version of which is 4.10.1) - history v5 is only compatible with react-router-dom v6.

You have forgotten :

router: connectRouter(history), 

in your combineReducers()

If you use immutable you should import ConnectedRouter from 'connected-react-router/immutable'.