Wars of Arin
The Wars of Arin were a series of large-scale combats fought between 755 and 801 LC, between the Onyx Army, the forces of the Onyx Empire based in Arin, and the White Army, primarily part of the White Alliance centered in Kellan. The wars ended in the defeat and eventual breakup of the Onyx Empire.
At the time, the Onyx Empire was ruled by the wizard Keraptis. He was supported by the country of Garnath, ruled by Lord Zathmore, and at some points Tanilon, ruled by the drow general Daelras. On the other side were the various forces of the SouthLands, most notably the aggregated armies of the White Alliance, founded in the early days of the wars by Morley Pallianor. Kellan was joined by the Dwarves of the Thair Mountains led by Thorin Orchammer (and later Thorin Archer), the Humans of Braith under King Xorg (and later his sons Zorg and Borg), and the combined forces of Itaron led by Frida and Elawita.
Throughout the length of these wars, the Onyx Empire sought to expand its territory from its central point in Arin. At various points, they were able to conquer most of Tanilon as well as Lan-Zarek, and even parts of northern Kellan, but were always driven back. They were severely impeded by the Thair Mountains in the south and, to a lesser extent, the Onyl Mountains in the north. In the end, Keraptis declared an all-out offensive that began in 785 LC.
There is some debate over when the Wars of Arin truly began. Indeed, there is debate as to whether it was truly a series of wars, or one long war of aggression by the Onyx Empire. The first battle that all agree was part of the Wars is the Battle of Hommlet, which took place in 755. This incident saw a band of humanoids overwhelm the small village of Hommlet in southern Tanilon. The village was aided in its defense by a band of adventurers led by a paladin named Zorg and his friend, a ranger named Nielsen Arbat.
Nielsen came back from the adventure to his cousin Morley Pallianor, who was at that time a minor noble in southern Kellan, and told him of his adventure. Morley thought the livery Nielsen reported the humanoids wearing was familiar, so he looked back in his family records. He find that it was the same as that worn by creatures inhabiting an underground labyrinth which his brother, Murphy, was exploring at the time of his death a few months earlier.
Keraptis declares himself
Concerned by this new threat, Morley traveled north to Arain to meet with Zorg and his father, Xorg, the city's ruler. There, he learned that similar armies of humanoids had been responsible for the destruction of the city of Rinogor some years before. Over the next few years, the area around Arain came under attack repeatedly.
Xorg went to his old friend, Thorin Orchammer, the king of the Dwarves of the Thair Mountains, hoping that the two of them would be able to catch this new threat between the two armies. However, it turned out that, whoever was leading these armies, they had an almost limitless number of forces.
In the meantime, a number of powerful magical items were being stolen across Lanad i'Sarois. Cryptic messages were sent to the rulers of the lands around Arin that the items could be found at Mt. Esterrin, deep inside what was now considered enemy territory. A band of adventurers, led by Zorg and Roderick Harper, was sent to retrieve them, but they got more than they expected, as the power behind the threat revealed himself as Keraptis, a wizard who had long been thought dead after his flight from the destruction of the Purple Castle.
The White Alliance forms
Following this revelation, Tristan I, the king of Kellan, finally listened to Lord Morley and began working toward building an alliance with the surrounding lands. The first city to be approached was Hanmer, an important river port in central Kellan. Over time, a number of cities around Kellan joined the burgeoning alliance, and a council -- the White Council -- was appointed to coordinate the military activities of the realms. Nielsen was appointed the alliance's first general.
The empire split its army into two parts. The northern force, commanded by Zathmore, was charged with capturing Alior and moving through the Gap of Veclin to attack the northern part of Tanilon and, eventually, Jar-Kahn, which was controlling much of the northern forces behind the scenes, led by Gandriel. The southern force, meanwhile, was led by Morjec, another wizard loyal to Keraptis.
The southern front
In the south, Morjec led a was able to make an end-run around the Thair, marching through Lan-Zarek, then coming down the Vorilon River into Kellan. He was aided in this by his use of the Kellanic Catacombs to send divisions of his army directly into Kellan through the UnderWorld. In the east, a force led by Rarth Ilinix was given passage through Cardyl in exchange for a treaty of nonaggression, allowing the Onyx forces to take the city of Byngh and make forays into the Filitir Forest.
Morjec's forces took the city of Hanmer, and decided to move again against Kimelis, which they had tried and failed to take some years earlier. However, the city's defenses held at the Battle of Kimelis with the aid of reinforcements from Morelenas, and the combined troops, led by Roderick Harper, were able to beat the Onyx forces across Kellan and drive the eastern forces out of the Filitir, leading to Ilinix's capture by Thorin's army.
The northern front
In the north, things did not go well nearly from the beginning. While Zathmore conquered Alior with relative ease, the Gap of Veclin held fast. Further to the east, Eliendis also offered stiff resistance. At that point, Keraptis made a fateful decision: to cut off support for Zathmore and focus on the faltering southern front.
This proved to be a tactical error, as Zathmore turned on his master, attacking Arin from the north. Keraptis had to call back his forces to defend against the traitor, allowing the SouthLands to regroup and begin pushing back. While Zathmore was defeated relatively quickly, and Daelras given command of the northern army, the opening was enough for the fledgling White Alliance to take advantage. It is thought that, in the end, the Empire simply overextended itself, leaving itself open to attack in its home territory of Arin.
The wars essentially came to an end upon the Empire's defeat in 801, after which Keraptis himself was hunted down and (presumably) slain by a band of high-ranking soldiers. While no peace treaty was signed, the region of Arin had been laid waste, and the army broken and scattered, but the forces allied against it were weakened, and thus were content that the invaders pulled back to their base. One of Keraptis' old minions, Morjec, came to power there not long afterwards, and it is thought he may be close to launching yet another attempt to conquer all of Lanad i'Sarois.