The book of Revelation seems to describe wars and violence on earth, but this misses the point. The real story of the book is spiritual. John saw a series of events on earth that would lead to a massive defeat of the spiritual powers of evil in the spiritual realms.
We assume that the last battle described in the book of revelation is a battle between the nations of the world. It is commonly assume that the armies of the nations will gather to attack Israel. This is part of the story, but the real battle is the battle in the spiritual realms. This battle will be decisive in history.
The spiritual powers of evil will gather from all over the world, attracted by the violence and destruction of war. They will be defeated and destroyed by the power of God. Just as they were created by God’s word in the beginning, they will be destroyed by Jesus’ word on that day.
The result of this victory will be a massively reduced number of evil spirits left to work in the world. With a much weakened spiritual enemy, the Holy Spirit and his angels will be free to advance the Kingdom of God in a powerful way.
Many popular books explaining the Revelation of John focus on wars between nations. They attempt to identify the nations involved in these struggles. This is pointless, because Revelation describes a spiritual war. To understand Revelation, we must read the book as primarily a description of events in the spiritual realms.