Revelation 6 tells us what happens as the Lamb opens the first 6 seals on the scroll.
The first four opened seals result in the appearance of horses. First, a white horse of military conquest. Second, a red horse of war. Third, a black horse of scarcity and inflation. Fourth, a pale horse of death.
The fifth seal prompts the martyrs in heaven to ask, "How long?" The answer is apparently "Not yet," as they are given white robes and told to wait - until their number should be complete.
A cataclysmic earthquake occurs with the breaking of the sixth seal. Signs appear in the heavens as the sun turns black and the moon turns blood red. The result is that everyone is filled with terror and trepidation about the judgment that has come upon the earth for the day of the Lamb's wrath has arrived.
Are these sequential events of what will happen in the end-times? Are they part of a pattern of history? Are they descriptions of a larger cycle? I encourage you to approach Revelation with prayer and wisdom, and a healthy measure of humility about conclusions that you may draw about timing and specifics. This book was written to the church nearly 2000 years ago, and it has spoken to every generation of Christians since then. There has always been a message for them (and us!) to hear, even if we are not among that final generation of believers.
But then again, we may be...