The Overgods are created.
The goodly Gods make the ultimate sacrifice and create Sigil. This blocks entry to the prime material plane by creatures from the planes on the astral sea. There are many exceptions but this move relieves the material plane from the vast majority of celestials and fiends. In response, the demons carve out the River Styx to continue their quest of domination.
The Gods create the Nine Hells to stage their forward base of operations in the Blood War. Just as the demons corrupted Mechanus over time, the Angel Army is being corrupted and creating Devils. The goodly Gods want them out of Mechanus and Celestia. They want to move the front line away from their homes.
The Batrachi end up in a war with the Titans of the north. They use ancient magic to release some Primordials to fight the Titans. The God Asgorath intervened to direct an ice moon to strike the planet in an event called the 'Tearfall'. This event causes huge destruction to the planet. The God Helios intervenes and sunders the prime material plane into 3 different planes. The Feywild and Shadowfell are formed from the Prime and the Primordials move into these other planes, leaving the Prime for the Gods.
The giants and dragons reach a truce after both their populations and kingdoms are shadows of their former selves. The elves create the Dracorage Mythal which is attacked by the dragons. The Avariel (Winged Elves) are almost made extinct during their defence of the mythal. The magic in the mythal is then transferred to Halley's Comet causing the first rage of dragons.
The High Elves use sundering magic to create the island of Evermeet. This causes huge destruction and changes to the land masses over the world. Meanwhile, Lolth seduces the Dark Elves and takes their leader Ka'Narlist as her consort. Some Dark Elves begin worshiping Ghaunadaur. The Sea Elves construct their undersea capital of Aryselmalyr.
Aryvandaar, now known as the Vyshaantar Empire wages war on Shantel Othreirer. Miyeritar is engulfed in killing storms which reduces the area to wasteland in three months. This was called the Dark Disaster and it is believed Aryvandaar mages caused this. Four centuries of peace is made from the shock and awe of the Dark Disaster.
Ilythiir’s counter attack to avenge Miyeritar sees the Dark Elves use the corrupt powers of Lolth and Ghaunadaur in the open for the first time. Shantel Orthreier is destroyed in flame. The Aryvandaar priests prayed to Corellon and his magic was channeled through them to turn the Dark Elves into Drow and make them sensitive to sunlight. Over two months, the Drow descended into the Underdark. Aryvandaar take over everything other than Keltormir.
The fragile peace was shattered when the Corellon Larethian mandated Elven Court decreed that the Sun Elf clan of Vyshaan was responsible for the thousands of years of war. The Vyshaantar Empire disputed the charges and madly declared war on everyone. Within 200 years, the ancient kingdom of Aryvandaar was no more.
A relatively peaceful time when various humanoid civilisations thrived in the absence of elven interference. The most populous races included humans, dwarves, gnomes, and halflings. Most of the Gold/Sun Elves moved to Evermeet. The Copper/Wood Elves stayed in their forest kingdoms. The Copper/Wild Elves remained elusive. The Silver/Moon Elves spread everywhere; some went to Evermeet, others went to live with the Wood Elves, and some integrated with humans. Most half-elves are from a Silver/Moon background.