The Preterist view: They see this passage as the preparation of defeat for Jerusalem and/or Rome. Euphrates is a historical reference to being conquered by surprise (the way Cyrus conquered Babylon), and as a metaphor to show how God will bring judgment when we are not expecting it, either to Jerusalem in 70 A.D. or the fall of Rome. They also see this as fulfilling Daniel’s vision and the beginning of the Kingdom of God. The troops that took siege of Jerusalem, according to Josephus, came from the region of the Euphrates. Frogs are seen as unclean and represent unclean Jerusalem or the allies of the Roman armies, why God destroyed it, and who he used. Kings of the earth and Armageddon are seen as symbolic for God being “pregnant” with judgment and ready to give birth to it as Elijah demonstrated near the same location when he defeated the false prophets on Mt. Carmel. Others see it as the destruction of Jerusalem or Rome. Come like a thief is seen as surprise as the Jewish and/or Rome leadership led to their doom (Matt. 16:28). It is done is the anticipation and finality of Jerusalem or Rome. Babylon is often associated as Rome by the Early Church, hence the reason for this position along with Matt 16 and 24. Some in this camp see this as Jerusalem because of the apostasy. Hundred pounds is seen as the siege engines that Rome used.
The Futurist view: They see this passage as the antichrist causing World War III and the details to this battle of Armageddon which they see as taking place (even though Scripture may tell us otherwise). They see God removing the Euphrates so Russia and China can attack Israel. Kings of the earth/east is seen as the literal attack of the Orient and/or China, or the Middle East collectively, and the rise of a new world order—a singular, oppressive government. Frogs are seen as modern war machines. (What would a tank look like to John?) This is correlated to Daniel 11: 40-45. Come like a thief is seen as a post-tribulation rapture or the coming of Christ. The seventh bowl is seen as the destruction of Satan and his minion. The Earthquakes are seen as nuclear war or a literal earthquake beyond measure. Babylon is seen as having been rebuilt and then destroyed, or the evil, spiritual, religious system under judgment. Hail is seen as literal or military ordnances.
The Idealist view: They see this passage as the fears of the Seven Churches for the pending Parthian invasion. Others see this as Nero’s suicide and the upheavals that occurred for the early Church that led to the escalation of persecution until Rome was Christianized and finally judged. Others at that time saw this as Nero coming back for vindication to the Church (Nero Redivivus myth). Others see this as the fall of Rome by the invasion of the Barbarians for the western kingdom and the Parthian invasion for the eastern kingdom. Euphrates symbolizes obstruction and how it will be removed fugitively. Kings of the earth/east is seen as our fight against God, our ways versus His Way. Come like a thief is seen as Christ returning and how unexpected it will be. Armageddon and the rest of the imagery is a representation of slaughter as in the judgments of God upon the wicked who refuse to repent.
The Historicist view: They see this passage as the Turks invading former Rome and the preceding southern European powers. Euphrates was a symbol for Turks and Muslim invaders from the fall of Rome until the 19th century. Others see this as God’s judgment on the corrupt papacy in the 16th through the 18th centuries. The river being dried up is their power coming to an end and the rise of the Reformation. Others see this as the decline of the power of the Turks in the early 19th century. Frogs and demons are seen as the wars and turmoil of the 18th through 19th centuries in Europe. Armageddon is seen as a symbol for conflict such as “The Great War,” WW I and/or our spiritual conflicts. They agree with the futurists that the seventh bowl has not been poured out yet. This is the final, climatic end of humanity and its fight against God. Others see it as a future conflict with Russia and the west, because another name for Russia is “Gog;” or, it could be the conflicts of the papal kingdoms, the Holy Roman Empire of past. Earthquakes and the other imagery are seen as man’s political powers and kingdoms clashing and coming to an end before Christ’s return. Babylon, in this view, is seen as Catholic Rome; splitting into three is seen as the final end of the papacy.