Everglades History

Ten thousand years ago it was all under water. What emerged through the centuries gradually took on the characteristics of tidal marsh, mangrove swamp, fen, lake and finally scattered uplands with hardwood trees. The early life of the water, of the land and of the sky must have made the region an incredible semi-tropical Eden. The Everglades muckland -- the largest single body of highly productive organic soil in the world--was fashioned through the centuries by decayed animal and vegetable substance and fertilized by vast hordes and varieties of wildlife.
William Roy Shelton, Land of the Everglades, 1957

The first known use of the term Everglades is on Turner's map of Florida (1823) and is cited in the Dictionary of American English currently being published by the University of Chicago Press. A map of Florida compiled by an English geographer for the British government and dated 1821 does not show the Everglades. The word seems to have come into use in Florida only after acquisition by the United States in 1819. The Spanish seem to have had no equivalent of 'Everglades'.

An early spelling was 'glad' and it meant bright, shining. 'Glade' in a sense now obsolete except in poetry meant 'a clear place in the sky, a bright streak or patch of light.
Marjory Stoneman Douglas
Everglades and First Reclamation Idea