During the Second Republic human colonists tried to take the planet for themselves and were soundly beaten by Vau military forces. A diplomatic solution divided the planet between the two parties allowing a limited human colonization.
The Vau reside on one continent and occasional visit the human sectors. Humans are forbidden from entering the Vau sectors, where the G'nesh live all but undisturbed.
The local operatives of the Imperial Eye seek to observe and to analyze the Vau. They rarely glean anything useful and a 'mission to Apshai' is often perceived as a vacation or early retirement.