Players who are able to adventure themselves in Azj-Kahet on the War Within Alpha may have noticed shadecasters scattered through the zone — Communicators that broadcast orders from their superiors. Some shadecasters are very old, and give us insight to an event of the past.
Two specific shadecasters give us insights of Anub'arak, the last king of Azjol-Nerub, and his efforts as he fought against the Lich King forces during the War of the Spider. We managed to find the two shadecasters, as well as an NPC of importance to these events!
In one of the forgotten shadecasters, we witness Anub'arak's pleas for help from the Kaheti empire. The communication suggests that this was not the first time Anub'arak reached out for help from the Kaheti. This shadecaster can be found by one of the nerubian towers in Anub'azal's Eye.
We do know that Anub'arak himself was the one who first launched the offensive against the then newly-formed Lich King, as a response to his bid of dominance of Northrend. The Nerubians had a fleeting advantage at first due to being immune to the plague of undeath, but the seemingly limitless forces of Undeath raised by the Lich King proved to be the enough to force the nerubian empire to retreat. This included managing to kill and raise Anub'arak himself as an undead, which helped speed the nerubians' retreat.
The remaining nerubians eventually saw themselves forced to dig deeper into the underground to retreat and reach safety, but they eventually accidently uncovered Faceless Ones, minions of the Old God Yogg-Saron. The nerubian empire, now cornered by both the Scourge forces and the faceless ones, ended up collapsing.