““Release the four angels who are bound at the great river Euphrates.” So the four angels, who had been prepared…, were released to kill a third of mankind.” Revelation 9:14-15
The Holy Angels of God are not restrained and go about in Heaven and Earth doing the good will of the Lord God. But these four angels in Revelation 9:14-15 have been bound along the river Euphrates in the Middle East. These are obviously four fallen angels who followed after the destructive ways of Satan, and as demons had been bound or restrained from doing their evil work of death. Then this prophecy in Revelation tells they are released at the great river Euphrates and they unleash themselves as demons of death going about their deathly work.
The Euphrates is now a river bounded by Islam. There are four Islamic countries whose land is at the River Euphrates; they are Turkey, Syria, Iraq and Iran. And as prophesied these four demons of death will work their demonic will with these four countries…
Interesting comparison