Nui-Vatur is one of the islands in the Southern Alliance. In the past, it is a very feudal society, ruled by a Duke and divided into three counties, each further divided into Baronies. However, a number of dangerous volcanic erruptions and earthquakes of natural origin devastated the island, leading to a disaster that killed almost ninety percent of the population in a matter of weeks.

Currently, Nui-Vatur is repopulating, though the entire island is still sundered. There are a few areas that were untouched, and the old barons and other nobles still rule the remaining areas. For the most part, Nui-Vatur is controlled by the Toa Council, who have been at the head of attempting to rebuild it. Council Chambers dot the landscape, including the largest one in the Southern Alliance, which is under the head of Master Toa Erashos.

Geographically, Nui-Vatur is covered by canyons and splintering cracks in the ground, and while it is still judged by the former landmass it had, nearly half of the actual island has sunk into the ocean, which tunnels across the island and gives it an otherworldly look. The coasts of the island are almost completely composed of cliffs rising high above the sea, and the few areas that aren't require navigating treacherous waters. Instead, Toa using the Stone and Earth elements often work in concert to rip away at the earth and create pathways and large gaps in the shelf to allow fishing villages to form and ports to be made.

Politically, Nui-Vaturs remaining nobles work with the Toa often, and a few have been bestowed knighthood by the current Duke or Counts for their actions. Unlike others in the Alliance, the Duke has refused almost all external help save for the Council, and especially refuses to be known as a Governor as some like Vamden have done.

While Nui-Vatur may have the greatest number of Toa of any alliance, the Primes found here outnumber them many times over - almost all of the ruling class or the warriors on the island are Primes of Pridak's species, though the majority of actual workers are Matoran.