From this victory; the true God could reshape the land and distribute among their followers, to bring peace and prosperity and happiness to all their people. This is not us. This is not man.
Mankind lost the war, or more accurately, our Gods did. The Lords of Light were beaten by the Red God; horny red-hot lustful Evil. The Father of all monsters, who could so lay with animals to create beastmen, and who released his seed into lakes and rivers to create the monsters that dwell there, and even he who took the most loathsome parts of all the most loathsome animals, filled its belly with fire to keep it warm, and so fucked the first dragon into being just to create something he found attractive. These monster races won the war, and their God was declared king over all.
Humans live in the caves, in the swamps, in the border places between the fertile lands and valleys. Humans still have territory, the good mortals still exist, but in some places our lands are only as wide as a tiny trail through the unfriendly forests. Those same docile beasts turn to murderous rage if they so much as smell a human, most birds caw and circle around any humans they spot, to draw monsters to us for easy slaughter. Even though they've grown fat and stupid, the monster races still despise humans and make it a sport to kill every last one of us, but they can take their time.
The good races still exist yes, but living however we can. Our warriors fashion weapons and armor with bones and pilfered steel, while the armies stride with legions of mithril. Our magicians must write with chalk and begin flaming spells with flint and tinder, while theirs have the pilfered and ancient libraries and scrolls of golden thread. We farm snails and slugs and mushrooms on tiny patches of dirt, while they waste food away by tossing it to dogs fatter then our Kings.
One day, we're going to take it.