One of the most populous drow civilizations, their capital city, Sia'Peiran, from where comes the name, was the third largest drow city, with about 90.000 inhabitants during the Middle Age of Human Dominion, and a total population of Sia'Peirans of around 310.000 drow.
The Sia'Peiran, under the rule of their Divine Queen -held in belief by the Sia'Peirans to be a reincarnation of the matron goddess of their peoples- came to be a drow empire, as they conquered the other drow city-states of the region.
Due the divine nature of the rulying dynasty, the nobility of Sia'Peiran didn't attempted coups to overthrow the queen, but this didn't meant that there weren't palace intrigues, and often after the passing out of the queen, that there would be a bloody sucession in the palace before a new Divine Queen was revealed.
While the regional governors where elected by the Divine Queen, often the Queen had to choose them from regional nobility, and while they were to be dependant of the Divine Queen, in fact there existed powerful local dinasties that held these regional seats of power. Some of the more determined and powerful Divine Queens will try to transplant some of these noble families to other regions, to ensure their loyalty was to the Divine Queen, rather than their own goals, having to rule over foreign subjects rather than their countrydrow.
The Sia'Peiran had a complex relation with the Sunner nomad drow tribes, using them sometimes against their enemies and rivals and paying them tributes to keep them from raiding Sia'Peiran territories: while the Sunner recogniced the divine nature of the Divine Queen, they didn't had a monolithic political structure and their stance toward Sia'Peiran shifted.
The Sia'Peiran were a very matriarchal society, in which with the passage of centuries, the males were more and more limited to private areas of society.
Some characteristic features of their clothing are the large robes they use that cover them almost completely, especially when they travel to the surface, and that the males are commanded to always use in public places, robes normally of yellow, orange and red colours, as well the use of sometimes green and light-blue colours, among others.
Despite their rejection of the Islamic religion of their human neighbors, the exchanges of knowledge and ideas have been important.
They were faced in wars several times by the Negeémi drows from the city-state of Negeémiliel.