I seem to recall reading that England were originally going to play in all white but the rugby team international side already were so it was decided to have dark blue shorts. Might not be true of course. Trouble is when they put red in you then get the colours of the union flag.
A red and white kit would be representative of our colours. Or maybe an all white kit with a red cross on the front and back. That would piss some off.
Edit - Seems they did play in all white for their first few games. Maybe they added navy blue shorts to distinguish themselves from the rugby team.Interesting to read that they originally had to provide their own shorts and up to the mid 1930s played in their club socks. I think that used to be the case with union, a tradition that carried on with the British Lions and Barbarians.
http://www.historicalkits.co.uk/international/england/england-1872-1960.html