Answer: The history of English gardening is a long and somewhat convoluted one in that it reflects many influences over the centuries. John Brookes "The Book of Garden Design" ISBN 0-02-516695-6 starts out with a good brief history of the major influences as does "Garden Design: History, Principles, Elements, Practice" ISBN 0-671-47993-8. Both of these are nicely illustrated. Any basic text on landscape architecture should give you a good introduction as well.
Sisely Garden Tours offers an interesting listing of people (and gardens they created) http://www.sissons.demon.co.uk/gardners.htm#wise with links to more detail about some of them. This might help bring it to life and give you a start at recognizing the major names.
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