Jess I'm afraid English nationalism is a minefield. Best if the English just keep their heads down for a few more centuries. It's never going to play well with the Celtic fringe, or any of the colonies - India, Australia, New Zealand, North America
Assuming the above is tongue-in-cheek! 
Wonder why it is called New South Wales ; the flagship department store in Sydney is called 'David Jones!
In fact it was the British not the English alone.
English nationalism is never going to be popular with other nations because they have always been top dog
Why is that I wonder?
Not feeling very top dog in Wales any more, in fact some Welsh become very belligerent if you say you are English, or make kind but patronising remarks as if to say 'well, you can't help where you were born'.
I think the English should start to reclaim a pride in their nation. A national dress, national festivals and a new national anthem for England alone.