• c. -33800 DR
  • Fall of Isstosseffifil:
    In an effort to drown the phaerimm of Phaerlin (known today as the Buried Realms in the Underdark) and dispatch their enemies in one masterful stroke, Isstossef wizards rerouted the Narrow Sea so that it ran from east to west, inundating the land around the chain of hills known today as the Tagorlar with water.  Although the Isstossef succeeded in driving the phaerimms deep into the Underdark, the massive ecological change resulting from their weavings of Art caused the Isstosseffifil empire to collapse.

    Although most of the sarrukh of Isstosseffifil died with the city's decline, many survived. The survivors retreated into lichdom in the depths of Oreme where they are protected by the asabis they had created. »

  • -30000 DR
  • Fall of the Aearee Empires
    The Time of Dragons is ushered in as dragons across Faerun swarm together in the first Flight of Dragons. They assail the avians in the air, on the land, and beneath the ground. They fall upon the home nest of Viakoo and burn the city from the sky.

    In the caverns beneath the Orsraun Mountains, the wyrm-general Nagamat rampages through the ancestral hatcheries of Shara and claims the kingdom as his own. Using the found magic, Nagamat founds the first dragon kingdom. Sharan aearee survivors escape deeper into the Underdark, where the feral and twisted descendants of the Aearee-Quor become the dire corbies.

    The survivors of Viakoo flee west across the ocean to the land called Anchorome. Five of their cities, all crafted from spelljamming helms, flee to the stars. Rulungwar, Donnakee, Phra'iskree, Oolatiel, and an unnamed fifth one, lost during the exodus, crosses the Sea of Night to the world of Coliar. These aeries float there still, among Coliar's manifold moons. Descendants of Aearee-Krocaa are known today as the aarakocra.

    Some few repentant Aearee-Quor begs Quorlinn for his mercy, and he leads them to Kara-Tur to find refuge with their long lost cousins of Tiennkoo-Shara, the tengu. Descendants of these people call themselves kenku. »

  • -10000 DR
  • Descent of the Drow; End of the Forth Crown War
    Corellon's magic, as directed through his priests and High Mages, transforms the dark elves, whether the corrupt Ilythiiri or others, into the drow. Whether by magic or by the weaknesses that banish them from the sunlit lands, all drow retreat within two months' passing into the Underdark. »

  • c. -9600 DR
  • Rise of the first drow civilizations in the Underdark beneath southern Faerun and the founding of the drow cities of Telantiwar and Guallidurth. The constant harassment of the Vyshantaar forces over the next five centuries help prevent their annexing Keltormir or any other lands. »

  • c. -8500 DR
  • Dwarves migrate north from the Great Rift and enter the cavernous realms beneath the Sword Coast South. »

  • c. -4000 DR
  • The duergar rebel against their illithid masters and eventually free themselves of the mind flayer's dominion. These newly liberated gray dwarves carve out their own holdings in the northern Underdark, beneath the Orsraun Mountains, and in isolated caverns deep beneath the Great Glacier. »

  • -3717 DR
  • Gray dwarves found Gracklstugh, City of Blades. The first city of its kind in the North, its holdings grow without rival throughout the upper and middle Underdark. »

  • -3419 DR to -3416 DR
  • The Netherese approuch the dwarves of Delzoun at Ascore to conduct trade. After three years of deliberation, a trade route known as the Lowroad running through the safest and most heavily patrolled sections of the Underdark, linking Delzoun to Netherese towns, is established. »

  • c. -3000 DR
  • Sloopdilmonpolop, the City of Pools, is founded by the kuo-toas in the Underdark off the coast of Tethyr. »

  • -2488 DR
  • Lord Ilphemon and a small group of family and retainers flee into a uncharted corner of the Underdark, hoping to escape the fall of the Imaskar Empire and the wrathful Mulan slave armies. Ilphemon's descendants eventually rule Deep Imaskar for many centuries as kings and queens. »

  • -2481 DR
  • Ilphemon, an Imaskari lord, founds the hidden city of Deep Imaskar in the Earthroot area of the Underdark. »

  • -1850 DR
  • Under the leadership of their greatest queen, Duerra, the gray dwarves of Underspires launch a series of attacks against their Underdark enemies, the drow of Undraeth, the illithids of Oryndoll, and eventually the remnants of Deep Shanatar. »

  • -1400 DR
  • Start of the Eleventh Rysar of Rystall Wood. Coronal Faahresc is a rabid drow-hating warrior who leads his people on numerous raids in the Underdark caverns and the Twisted Tower to the south. »

  • -736 DR
  • Tulan el Akada's forty most loyal aranea remain Calimport and take up residence in hidden byways beneath the city and among caverns in the upper regions of the Underdark (former scouting posts of Shanatar). They begin fortifying the defenses of Calimport against the drow and making a home for themselves in the dark areas where few sadimmin (Calishite soldiers) wish to tread. »

  • -690 DR [Year of Fragile Beginnings]
  • Blingdenstone, a deep gnome community, is founded in the North Underdark by svirfneblin fleeing phaerimm expansion. The deep gnomes establish their settlement despite its close proximity to Menzoberranzan, lured by the rich veins of arandur (a metal that holds its sharpness particularly well), iron and rubies. »

  • -664 DR [Year of Turning Tides]
  • The drow nearly destroy the town of Keltar in Calimshan over the course of a 37-hour battle, given their magical superiority and a globe of darkness that they use to surround the city. Calimport's army arrives after the drow conquer the city and have shipped more than half of the surviving population into the Underdark as slaves. Although the Calimshites free the town and force the drow back to the Underdark, more than 3,000 Keltams are never seen again. »

  • -649 DR [Year of Falling Copper]
  • Large parts of Calimport are purposely destroyed to bury the drow temples and partially subterranean villas, but some remain relatively intact though buried. Those same wizards who burned the city help rebuild it and seal off all areas between Calimport and the Underdark with stone and new buildings. Despite their diligence, the drow reopen those passages within a decade and reestablish their hold on Calimport Below, the Muzad, now nicely protected by the city overhead. »

  • -351 DR [Year of Dark Roads]
  • As the life-draining spells of the phaerimms rapidly despoil central Netheril, several Netherese arcanists abandon their demisnes and begin searching for a place to build a city in the Underdark, beneath the western wilderness. »

  • -339 DR [Year of Sundered Webs]
  • Ioulaum of Netheril abandons his floating city for his lair in the depths of the Northdark while civil unrest peaks in Low Netheril. »

  • Establishment of the Netherese survivor states of Anauria, Asram, and Hlondeth as well as the underground city of Philock in the middle Underdark beneath of the Wood of Sharp Teeth. »

  • -331 DR [Year of Shadows Fleeting]
  • The elf armies of the Coronals Tannivh of Cormanthyr and Connak of Rystall Wood finally break the greater defenses of the Twisted Tower (near present-day Shadowdale) and destroy all remaining drow slavers within the tower. The tower is left in the hands of good dark elf allies, and it is a great temple to Eilistraee within a century. The Soldier's Blade is lost during this great battle, captured by the drow in their slaying of Lord Orym Hawksong during the fall of the Twisted Tower. The blade and the body of Lord Orym are taken down into the Underdark as spoils of war by the fleeing drow. »