In appearance the locusts were like horses prepared for battle: on their heads were what looked like crowns of gold; their faces were like human faces, their hair like women’s hair, and their teeth like lions’ teeth; they had breastplates like breastplates of iron, and the noise of their wings was like the noise of many chariots with horses rushing into battle. They have tails and stings like scorpions, and their power to hurt people for five months is in their tails. They have as king over them the angel of the bottomless pit. His name in Hebrew is Abaddon, and in Greek he is called Apollyon. Revelation 9:7-11
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), and 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 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, capital 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.
To be continued …
Update: continued in Revelation 9: the sixth trumpet