In Europe this butterfly only occurs in SE Europe as far west as Austria (where it is now thought to be extinct). Eastwards it occurs as far as Korea and Japan (albeit as different sub-species).
The butterfly can be quite common where it occus but it is quite elusive and can be difficult to see. It spends a lot of time in the crowns of trees sitting on the leaves or branches, especially in hot weather (a pair of binoculars can be very helpful in spotting them), males flying off from time to time to chase or inspect another butterfly flying nearby. Males will descend to the ground to feed on damp bare ground such as sand bars on the exposed riverbed. They may also be found on dung, carrion or at sap suns on the hostplant.
Freyer's Purple Emperor is very similar to, and can easily be confused with, the orange form of the Lesser Purple Emperor (Apatura ilia) (f. clytie). In our experience the latter species seems to be much less common in Bulgaria. I think all the above are Freyer's Purple Emperor!
It is found near rivers and streams where its hostplant White Willow grows. It occurs up to over 700m a.s.l. (one probably this species at about 900m near Dobrinishte)
Adults can sometimes be found flying around or resting on young willow bushes.
Widespread in Bulgaria but local.
Recorded in 20 (1.1%) of the 1900 10km squares of Bulgaria.
Last recorded in June 2019
Recorded date range (Adult): 23 May to 09 August