Here's something to consider. At the time of John, the Roman Empire was in power, thus the angel spoke regarding the seven heads that 'five are fallen and one is'.
The 'one is' is the Roman of course. Now, the angel also said that the beast 'was, and is not'.
Which means that it could not be the Roman. Roman 'is', while the beast kingdom 'was, and is not'.
That makes the beast kingdom one of the five that are fallen. And that simply to show, I believe, where the ac will arise from, that being Turkey.
Irregardless, all eight heads are from the same single beast, who gets his power from the dragon. All eight are influenced, controlled, by Satan.
The seven hills that the beast sits on are not literal physical hills, but rather is an allusion to the seven empires, and their seven kings