The Tollanaugh Empire was a massive construct, the immediate predecessor of the Dulama Empire. Among the western powers, the Tollanaugh were traditionally the westernmost, hailing from the Sunset Coasts; they existed for years on the outskirts of the much older and much larger Amure Empire before a spectacular campaign brought the Amure down in a single fell swoop, and almost all the Taidhe came under their control.
In the end, of course, it was not to last. Cairl the Great, Emperor of the Dulama and a military reformer and genius both, started a series of campaigns stretched out over a decade. From the highlands around the city of Dula, the Dulama swept down the River Abrea, then up the River Thala, breaking the back of the Tollanaugh and establishing the newest great empire of the west. All in all, the Tollanaugh's dominance had lasted less than four decades, though a rump state remained in their traditional homeland in the extreme west. This rump state would eventually evolve into the small nation of Ther, whose leaders still dream of their imperial history. That legacy has aided Ther in long retaining its precarious independence as a minor state in the face of much larger and more powerful neighbors.
Although the Tollanaugh Empire was short-lived, it was during the reign of the Tollanaugh emperors that Machaianism, long a faith confined to the far west, spread like wildfire through the heart of the former Amure Empire, which previously had followed a sacrifical religion reminiscent of the Dulama religion. Thus, the cultural impact of the Tollanaugh far outlasted its political strength.