The War of Many Banners was a 20 year war lasting from year 676 to year 696 of the Fourth Age. The war was the result of the expansion of the Empire of Xeilias into lands inhabited by various Clans ("The Scattered Lands") that would later band together and become the Kingdom of Vornair. During the war the Empire was frequently identified by its armies' banner, that of a black snake in a circle on a white field, or commonly referred to as "The Black Snake Army" or many other terms.
In the early years of the war Clan Rhyne began a unification of the Clans, Tribes, and Houses that were being conquered. This unification would later be known as "Rhyne's Call". Though some of the Clans were able to hold their ground, many were beaten or displaced from their homelands. It was not until after Clan Rhyne unified the clans that the Empire found themselves being pushed back into its regions of origin.
The war culminated in the final battle of The Siege of Archeon. During this battle, it became clear to the Empire that the Clans were forming into a force to be reckoned with and that Conquest, at least at this time, would be impossible. Following this battle the Xeilias Empire withdrew from the lands and extended a truce to Clan Rhyne, the apparent leaders of the allied clans. Though they did in fact retain some of its conquered land, that of the clans that did not answer Rhyne's Call, the expansion was not as successful for the Empire as they had previously expected.
Following the war, the allied clans praised Clan Rhyne for it's leadership and steadfast determination. Two years after The Siege of Archeon, the clans would raise Clan Rhyne to the position of King and the Kingdom of Vornair was born.