The shape of the locusts was like horses prepared for battle. On their heads were crowns of something like gold, and their faces were like the faces of men. They had hair like women’s hair, and their teeth were like lions’ teeth. And they had breastplates like breastplates of iron, and the sound of their wings was like the sound of chariots with many horses running into battle. They had tails like scorpions, and there were stings in their tails. Their power was to hurt men five months. Rev 9:7-10
As to the appearance of the army of locusts, Barnes Notes on the New Testament does an excellent job explaining all the details. The Mohammedans rode on horses, and had long hair like a woman’s (which was probably an unusual sight for John, who had only seen Roman warriors), with yellow turbans on their heads. They were so expert riders, that while they were fleeing the enemy, they could turn in their saddles and shoot behind them accurately with their bows and arrows, thus their tails had stings like scorpions.
The first four trumpets were to strike one- third of the Empire, and we supposed, then, that the fifth trumpet was to strike a second third of the Empire. Here is our map of the Roman Empire again. The barbarian invasions — the first four trumpets — took over the old territory of the Roman Empire from Britain to Italy, or all of Western Europe. That is the first third.
The rise of the Islamic Empire took over the old territory of the Roman Empire from Arabia north through the Levant and Syria, and west through North Africa and Spain. That is the second third.
The territory that is left is Asia Minor, Greece, and southern Eastern Europe: the final third of the old Roman Empire. At the end of the Islamic conquests in 762, this territory was still in the hands of the Roman, or Byzantine, emperor of the East, whose capital was at Constantinople. We would predict that the sixth trumpet to come will strike that territory, and that it will not begin until after 762, at least.
revelation 9, the four angels of the sixth trumpet
revelation 9, the sixth trumpet: crossing the euphrates
revelation 9, the duration of the sixth trumpet
revelation 9, the sixth trumpet army
revelation 9, the trumpets did not inspire repentance
My book The Revelation of Jesus Christ Revealed, based on these studies but greatly expanded, is now available at Revelation Revealed Online. You may also be interested in reading the Book Extras and joining in on the Discussion.