The last chapter described the throne room in heaven where we saw the book with seven seals given to the Lamb. Only the Lamb of God was able to open the seals, resulting in the events which were foretold from John’s time on, as the pages of the book were opened. These seals were opened in succession and with the opening of each seal John saw and recorded an impressive vision. No system of interpretation that doesn’t represent these as chronologically successive events is reasonable. The vision following the opening of the first seal must portray a period of events nearest to the time of John, and the rest follow in order describing the history of the church and of the fate of the world.
The first four seals, that follow here, are all similar in their imagery and can only be reasonably explained as symbolic references to events in the history of the fall of the Roman Empire. The Horsemen are not representative of individuals, but of great epochs, periods in history.
The Lamb of God, Jesus Christ, opens the first seal (v.1)