Puuea'ikuhhi Earth, once called Juukanuzk by the Empire of the Combine Race, is a version of Earth inhabited by Humans and a collection of species dubbed Monsters. Pier to the 2376 incident, the planet society was noticeably bleak, while the inhabitants reacted in ways that seem to indicate the opposite, even when they were committing things that to most other universes (or just planets in their universe) would regard as immoral and unethical. But, following the destruction and death brought by the secret purge facility buried on the planet by the ECR, the planets' society and culture changed radically, with both groups creating a more just, moral and ethical society in the process. The Alliance would then discover the planet in 2376 shortly after the incident with Purge Facility Kappa, and it was the first true time the Alliance has gotten any concept of the Emperor's Final Order's and the extent of the damage they could do and quickly began to aid the planet's recovery.
In the process of the Alliance's reconstruction of the planet, the population came into contact with the Cult of the Nine Arches and it, in turn, would quickly adopt the religion across the planet, be they Human or the various Monsters species.
It should be noted that the planet is a Plains of Rebirth borderworld, which often explains the often bizarre way the planet's environment and population works.