18th CSR was the century between 1701 SR and 1800 SR according to the dantrian calendar.

In the east it was marked by a decrease of Yammoe's influence in the northern regions, which would continue for the next century and would eventually result in Yammoe withdrawing from the region completely.

Osa Nara began to dominate the northern region, mostly due to Xornerian's autocracy entering into a period of civil wars, which resulted in the state effectively failing. Both countries were conquered by the Kareden in the 1780s.

Kareden first appear in history, through their erratic conquests in central and northern Tarnaria. They steadily moved north and then turned towards Loodon and Makam rivers, instigating a series of conquests. A Kareden Kingdom of Mamkoon was formed, with King Anashary emerging as a powerful ruler.