» Thu Oct 29, 2009 9:56 pm
Yes Cyrodiil was once a jungle, evidence of this is found in the http://imperial-library.info/content/pocket-guide-empire-first-edition-cyrodiil:
...It is the largest region of the continent, and most is endless jungle. Its center, the grassland of the Nibenay Valley, is enclosed by an equatorial rain forest and broken up by rivers. As one travels south along these rivers, the more subtropical it becomes, until finally the land gives way to the swamps of Argonia and the placid waters of the Topal Bay. The elevation rises gradually to the west and sharply to the north. Between its western coast and its central valley there are all manner of deciduous forest and mangroves, becoming sparser towards the ocean. The western coast is a wet-dry area, and from Rihad border to Anvil to the northernmost Valenwood villages forest fires are common in summer. There are a few major roads to the west, river paths to the north, and even a canopy tunnel to the Velothi Mountains, but most of Cyrodiil is a river-based society surrounded by jungle.
Also the the ingame book, from both Oblivion and Morrowind, http://imperial-library.info/content/provinces-tamriel mentions Jungles and rain forests to a lesser degree:
....Cyrodiil is the cradle of Human Imperial high culture on Tamriel. It is the largest region of the continent, and most is endless jungle. The Imperial City is in the heartland, the fertile Nibenay Valley. The densely populated central valley is surrounded by wild rain forests drained by great rivers into the swamps of Argonia and Topal Bay. The land rises gradually to the west and sharply to the north. Between its western coast and its central valley are deciduous forests and mangrove swamps.
However MK wrote http://imperial-library.info/content/many-headed-talos to explain the change:
"And after the throne of Alinor did finally break at the feet of Men, and news of it came to the Dragon Emperor in Cyrodiil, he gathered his captains and spoke to them, saying:
"'You have suffered for me to win this throne, and I see how you hate jungle. Let me show you the power of Talos Stormcrown, born of the North, where my breath is long winter. I breathe now, in royalty, and reshape this land which is mine. I do this for you, Red Legions, for I love you.'"