Something interesting that came to me a while back is the root of draining the swamp.

Anyone familiar with the Mists of Avalon? Did you know that the British Catholics drained the swamp?

" In 1630 the king granted the fourth Earl of Bedford the right to drain 95,000 acres traversed by the Rivers Nene and Great Ouse, stretching from Ely well to the north. Bedford, along with 13 fellow investors known as the Gentlemen Adventurers, hired the Dutch engineer Cornelius Vermuyden to work on the project from 1630 to 1655, with time off for civil war."

[link to britishheritage.com (secure)]