Lemuria was a chain of large islands in the ocean east of Thuria, and perhaps southwest of the Pictish Isles off the eastern Thurian coast, during the Thurian Age. They were somehow related to the people of Mu as they shared the same alphabet and perhaps alphabet. They had contact to a people of eastern Thuria, who came from a continent east of Lemuria (perhaps Mu).
Lemuria sank into the sea during the Cataclysm that ended the Thurian age. The Lemurians escaped to the east coast of the Thurian continent but were enslaved by that people, and endured a millenium of brutal slavery that reduced them to a state of savagery. They eventually rose up and destroyed their masters, and pushed them away to Stygia. The descendants of the Lemurians became the Hyrkanians.