- For the early history of the region, see Pronel.
The kingdom was established in 2857, during a period of weakness among the Xurnese, through the efforts of Sucunto, lord of Yewör, who became the first pažwa. The kingdom was first known as Püŋili ('Pronel'), but soon became known instead by the name of Sucunto’s dynasty, Cuoli.
As the rise of Xurno had demonstrated, the long dominion of the nomads was over. New military advances— plate armor, crossbows, explosives— had to be manufactured in cities, not nomad camps; and Xurno’s neighbors had learned from it how to build large circuits of fortifications round their cities, enabling them to resist seiges longer than the nomads’ patience allowed. It was the barbarians’ turn to be hassled; the early pažwã dedicated much time to bullying the Losainor, the heirs of the fearsome Sainor who had terrorized them for centuries.
In 3042 the pažwa Bṏlé inherited the principality of Evan, on the south shore of Lake Van. It was irresistably tempting to attempt to occupy the territory in between, the upper Xengi; and since the Xurnese were busy with the Revaudo civil war this proved possible, though it took ten years and required moving east rather than west of the lake. In the last battle Bṏlé won the country (from Revey upstream) and lost his life.
The succeeding pažwã extended this victory, occupying more Losainor territory, Tei, parts of Sevisor, and Bozan, culminating in the conquest of the upper Xengi from Rašageor to Sieš (3180). Cuoli now seemed to be a major power. 
In 3220 they saw an opportunity in the new confederation of Belšai. To everyone’s surprise, the Belšayin soundly defeated the invasion, and this made Cuoli’s other enemies bolder. The Losainor pushed back into their old territory west of Lake Lenan, and in 3240-60 the Xurnese reconquered the upper Xengi valley and some of Cuoli’s southern territories. The Cuolese empire was reduced to the environs of Evan as well as Bozan, and these were lost a century later (3352 and 3367 respectively).