They were first contacted in 565 by the Faowaou clan, then considered the most powerful clan of Tlaukhu Bloc-6 (all steaakh’s are set up by Bloc-6 Tlaukhu clans). By that time, their empire contained most of its current worlds, and was managed by sub-light ships.
In 567 the Faowaou suggested the creation of Steaakh Etra to the main Etra government at Oso, seeking resources from the Etra region, and possible further domination of the non-aligned worlds between the Iyestea and Foseakh Outstates. The Etra refused, and the Faowaou started sending troops to the Iyestea Outstate, where they had full control of numerous worlds, including the capital, Iyestea (2414 Fahreahluis) (this is now reduced to just Sehari (3104 Fahreahluis)). In 568, they had increased their presence in the local non-aligned worlds, including strategic system Ououtaed (0211 Hfiywitir). When they attempted to place units at Greposhandir (0710 Hfiywitir), the local government resisted, and they forcibly took control of the mainworld. This drew the dismay of the local Ui’royeah clan, as well as the Tralyeaeawi clan of Bloc-3, and the Faowaou had made a large amount of Aslan enemies in 568 when they took over a large number of worlds in the Iyestea Outstate. Over the next weeks, the Tralyeaeawi, assisted by the Ui’royeah, invaded the system and successfully freed Greposhandir. There were a few Etra ships in the system by coincidence, and they assisted the Tralyeaeawi, gaining the Etra a position of honour in the eyes of the Tralyeaeawi, who controlled (and still control) Urlal (2514 Fahreahluis), which is located just Jump-1 from Iyestea.
The Faowaou then launched a quick and rather unorganised mission directly into Etra lands. Upon their arrivals at Efe (0712 Hfiywitir) and Upper Oe (0613 Hfiywitir), despite being technologically superior to the Etra, they were swamped by Etra larvae, and the Tralyeaeawi, seeking to “come even” with the Etra for their help at Greposhandir.
The Faowaou were very quickly eliminated, leaving the Faowaou back in the Iyestea Outstate unknowing of the mission’s fate. Over the next few years (570-573) Tralyeaeawi then launched a series of diplomatic missions from Urlal, to limit the control of Iyestea and the other newly Faowaou-ruled worlds, and supplied the Etra with jump technology, which they used to quickly explore and gain support from many other Hfiywitir worlds. Then, in 574, the Etra, assisted by the Tralyeaeawi and other enemies of the Faowaou, invaded the Iyestea Outstate. By the end of that year, they had practical control over Etau, Ausewer, Keiaoeasea’ and a number of other worlds, as well as non-aligned Ououtaed and Meire. The Etra/Tralyeaeawi coalition then laid siege to Iyestea, and the Faowaou there sent out emergency messages to the Faowaou in the main part of the Hierate, and fellow Bloc-6 clans Iykyasea and Uiktawa. The Uiktawa were able to identify the “mysterious something that wipes out Aslan” (i.e. the larvae) as falling objects of some sort, and further missions used nets to shield the soldiers, and the combined forces of the clans ended the siege. In 575 this force also retook the Tralyeaeawi-controlled Aslan worlds, but the Faowaou’s status was significally impacted by their lack of ability to keep out the Tralyeaeawi and Etra, and they opted to (officially) withdraw most of their forces from the Iyestea Outstate and end their (official) hostilities against the Etra, but they have since then constantly tried to downplay the incident, and prevent clans unrelated to the conflict and outsiders (including the Imperials) from knowing about it at all.
When the Faowaou and the other Bloc-6’s established the Steaakh Yeasaol, the Etra defended the Yeasaol against hostilities (which aren’t supposed to be caused in steaakh by Aslan, but that’s in theory…), and have “interfered” in the goings-on of other steaakh and “Hierate Rim” states, even ones without “hostility” like the Steaakh Hlaia, and have gained an almost peacekeeper-like reputation is the Hierate Rim region.