Led by Usma bin Luai the Tayy invaded the mountains of Ajaa and Salma from Banu Assad and Banu Tamim in northern Arabia in their exodus from Yemen in 115 CE. These mountains are now known as the Shammar. The Tayy became nomadic camel-herders and horse-breeders in northern Nejd for centuries. Because of their strength and blood relations with the Yemenite dynasties that came to rule Syria (The Ghassanids) and Iraq (The Lakhmids), the Tayy expanded north into Iraq all the way to the capital at the time, Al-Hirah. The area of the two mountains subsequently came to be known as Jabal Shammar (Shammar's Mountain) from the 14th century, the first time that the Shammar as a tribe were noted in literature.