There never was such a thing as English traditional music, it's a big country(though it may not look like one from an American standpoint, say) with a lot of regions merging imperceptibly into each other.So a great performer with a Lancashire background will not necessarily tell you much about life on the Sussex downs.
   Having said that, I think there is one performer from the folk revival who most successfully constructed/invented/distilled something very very English from a lot of separate strands, and that is (alas,was) Tony Rose. He worshipped deeply at the shrine of the Tyne as a young lad, and successfully married those mannerisms with a very Somerset view of life, having picked up a load of other stuff along the way. I woud suggest a listen to what Tony did to "Just as the tide was flowing" and "Limbo" for examp[le, and then see what Eliza Carthy did to the same songs on "Anglicana"(nailing her colours firmly to the English mast).
   That sort of thing will give you a wonderful broad historical view of England.For a look at the England of my own lifetime, however, I'd always say Ray Davies and the Kinks hit the nail on the head.