Using nginx, I want to preserve the url, but actually load the same page no matter what. I will use the url with History.getState() to route the requests in my
History.getState()
Your original rewrite should almost work. I'm not sure why it would be redirecting, but I think what you really want is just
rewrite ^ /base.html break;
You should be able to put that in a location or directly in the server.