Colovia
"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...forest fires are common in summer..."
Nibenay
"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...but most of Cyrodiil is a river-based society surrounded by jungle...."
Colovians
"The Colovians today still possess much of the frontier spirit of their ancestors. They are uncomplicated, self-sufficient, hearty, and extremely loyal to one another. Whenever the East would tremble under the weakness of a leader, the Colovians would withdraw unto themselves, always believing they were keeping the national spirit safe until the storm passed...do not allow themselves the great expenditure of courtly life as is seen in the capital city. They prefer immaculate uniforms and stark standards hanging from the ceiling of their austere cliff-fortresses; to this day, they become a little perplexed when they must visit the grandly decorated assault of color that is the Emperor's Palace..."
Nibenese
"By contrast, the Eastern people of Cyrodiil relish in garish costumes, bizarre tapestries, tattoos, brandings, and elaborate ceremony. Closer to the wellspring of civilization, they are more given to philosophy and the evolution of ancient traditions. The Nibenese find the numinous in everything around them, and their different cults are too numerous to mention...To the Colovians, the ancestor worship and esoteric customs of the East can often be bizarre. Akaviri dragon-motifs are found in all quarters, from the high minaret bridges of the Imperial City to the paper hako skiffs that villagers use to wing their dead down the rivers. Thousands of workers ply the rice fields after the floodings, or clear the foliage of the surrounding jungle in the alternate seasons. Above them are the merchant-nobility, the temple priests and cult leaders, and the age-old aristocracy of the battlemages"
-Pocket Guide to the Empire, 1st Edition
This is not to bemoan the Cyrodiil that we did get, but to imagine one we could have gotten