In the Year of the Deep Wound, 582 DR, Tarag, a chieftain of the sea ogres, used the powers of the sword Ilbratha and his own battle strategies to conquer the western frontiers of the merfolk realm of Hmurrath. There, Tarag founded the two Axe Kingdoms of Khuur and Nmalk.
The merrow suffered a major defeat in the Battle of the Haunted Plains in the Year of the Coveted Briars, 654 DR. Following their defeat, four-fifths of all merrow in Serôs were forced to flee south to the other side of the Sharksbane Wall. The rest survived on the Hmur Plateau or living amidst the ruins on the Haunted Plains.
Three years of conflict culminated in the destruction of the Axe Kingdoms and the fall of the merrow to the merfolk of Hmurrath in the Year of the Volanth, 655 DR. This saw the end of merrow "civilization" in Serôs.