The Century War

The century war took place between the years of 883-984 New Common Age (NCA). The lead up to the conflict was predated by smaller petty conflicts between the non-unified elvish fiefdoms and the collection of countries that made up their borders. It eventually escalated into a war that involved The Coalition alongside many smaller countries, nations and independent islands that no longer exist. The catalyst for this event was a vision that the Elvish King received that told of an apocalyptic future made by the younger races of the world. This drove an effort to reunite the separated elvish peoples into one united front known as Valinȁrl Erthad or Valinȁrl. Within the first years of the war, they had successfully performed a Blitzkrieg into their bordering nations. They then consolidated this land and created an empire of united territories.
The conflict sparked an arcane arms race that escalated dramatically over the war's duration. Elvish territories created their infamous “black sites”: Mass prisons that developed chemical, biological and magical weapons through fatal tests on inmates.
For the duration of the war, Valinȁrl took possession of over 64 separate countries, most of which resided in the southern hemisphere. Towards the later half of the 10th century, these countries began to take advantage of the elves' overextension. They began a guerilla campaign against a much larger force and succeeded by hitting supply lines, liberating black sites & creating coups in occupied territories. This caused disruption to the Valinȁrl, however when Altus joined during the waning years, this was when the war became winnable for The Coalition, as they began to call themselves.  After the war and the subsequent dispersal of Valinȁrl, a lot of the smaller countries no longer had a population large enough to support itself, and so lands were either absorbed into larger countries or left to ruin.