The myriad gods viewed it favourably and their champions often performed many mighty deeds therein. Peoples were united in a golden age that seemingly lasted an eternity, and any evil or corruption, while still present, were kept at bay more than aptly.
Despite even the best wishes from the earliest of the divine overseers of mortal planes, entropy still prevailed. Thus, division slowly set in; First among the Elves, who became either prideful and lofty — cutting of their realms from those they deemed of lesser culture, or paranoid and reclusive — escaping to the woodlands and marshes. Then fell the clans of dwarfkind, who became jaded and bitter of those outside of their mountain keeps. Albeit some more tame in the rolling hills of the south remain friendly to outsiders, at arms length.
The reasons for the hiding Gnomes is almost at this point lost to history, but nonetheless they are scant seen in the world at large anymore. But increasing activity from Goblin-kin over the many decades has been prone to dark speculation.
Then fell the settlements of men, who up until this time had enjoyed a blissful accord with the other races due to their kind heart, loyalty and devotion to those they favoured. But even the strongest of walls can not hold a house aloft on its own.
They spread quickly, and became wary of other kinds and kiths who seemingly thought themselves better than the most mortal human race, or suspicious of those who seemed to hide away from otherwise honest business and inquiry.
Corruption breeds well in division and xenophobia, so evils and malice grew more powerful and commonplace in parts of the continents of Basilfall. Darker and more alien entities crept in and grew in power, and people more calloused and cruel.
Some forsook the plane altogether, and their worship decreased or even died out and were lost in the tides of time. Others seek to restore some of what was forgotten in the dividing of the world, to usher in a dawning age of order and harmony once again. But more still, from even farther planes than the depths of the hell-lands, see it as a chance to take control for themselves and use the realm for their own will and fancy.
And it shall never be again as it once was.