They were comprised of the two kindreds of Morwe and Nurwe: the Tatyarin-Avari and Nelyarin-Avari. For a long period of time they accepted Tuvo, an Avar of unknown origin, as their High-King, but after the Battle of Palisor Tuvo's reputation and influence faded and he withdrew underground to the springs of Helcanen. After Tuvo's retreat, an Avar lord known as Tareg led many Avari westwards, including the Windan, Penni and Kindi kindreds.
A few of the original Hisildi stayed at Helkanen, but soon split up into a Tatyarin and a Nelyarin faction - the Tatyar staying at Helkanen under leadership of their Queen Dardariann, and the Nelyar crossing the Orocarni, fleeing into the empty wild woods of the east and the Romenaer and forming realms in Carangalen, Talenturi, Cimonienemor and Uiven.
The Hisildi had preserved a very archaic form,of Avarin they called "Kvenïa".