Cataclysm

Near the end of the Great War in 745 YB, a mysterious magical explosion destroyed most of Marish. The terrifying event became known as the Cataclysm and led to the other nations signing a peace treaty the next year in fear of suffering a similar fate.
The Cataclysm ravaged most of Marish and turning it into the The Wastelands. The origins of the Cataclysm is debated throughout Xorik. The most popular theories are:

• Marishian arcanists tinkered with magic beyond their means and brought the Cataclysm upon themselves (popular theory in Thamar)
• One of the other nations developed a powerful super weapon and Marish was the first target
• A Thamarian variant of the first theory: Marishian unnatural love of the arcane pushed them to do unholy experiments that angered the gods. The Cataclysm was divine retribution