The Rhoynish Wars were a series of wars fought between the city-states of the Rhoynar and colonies of the Valyrian Freehold. The last of the wars, the Second Spice War, was fought a thousand years ago. In total, the series of conflicts spanned most of two and a half centuries. They are described in Beldecar's History of the Rhoynish Wars.
Although the expansion of the Valyrians into the western coastal regions of Essos was welcomed by the Rhoynar at first, the Valyrian outposts eventually became a threat to the great city-states of the Rhoyne. What began as disputes between the citizens of rivaling Valyrian and Rhoynish cities, grew into a series of short-lived and bloody wars. The first war was the First Turtle War, fought between Sar Mell and Volon Therys. Over the course of two and a half centuries, other wars were fought, including the War of Three Princes, the Second Turtle War, the Fisherman's War, the Salt War, the Third Turtle War, the War on Dagger Lake, and the Spice War, among many others.
The conflict escalated when Sarhoy was destroyed by the Valyrian dragonlords in the Second Spice War. The remaining five Rhoynish city-states were united by Prince Garin of Chroyane, to end the threat of the Valyrians once and for all. Garin achieved early successes at Selhorys, Valysar and Volon Therys, which caused the dragonlords in Valyria to concentrate their full attention and power on the Rhoynar as never before. After a massive battle outside Volantis involving three hundred dragons, Garin's army was crushed and he himself was captured. The cities of Sar Mell and Chroyane were sacked and their people enslaved.
In response, Princess Nymeria, the ruler of Ny Sar, quickly led her people out of Essos using whatever ships and barges they could find. The story of their flight became known as the ten thousand ships. Their refugee fleet wandered the lands of the Summer Sea for many years before eventually arriving in Dorne, the desert land in southern Westeros.