Nope! The choice of backend is entirely independent from the choice of front end. React pairs nicely with Django, Rails, Elixir, PHP... anything that can serve static files, basically :)
The only time it could start to matter is if you want to do server-side rendering of the React app, in order to serve complete static HTML for the first page load. It can matter for SEO and page load speed. If you need SSR, you need a backend that supports it. It looks like it's at least possible with Django, according to a 30-second google search: https://github.com/nielslerches/django-react-ssr (ymmv, that repo has 4 stars, so I dunno :)
The only time it could start to matter is if you want to do server-side rendering of the React app, in order to serve complete static HTML for the first page load. It can matter for SEO and page load speed. If you need SSR, you need a backend that supports it. It looks like it's at least possible with Django, according to a 30-second google search: https://github.com/nielslerches/django-react-ssr (ymmv, that repo has 4 stars, so I dunno :)