The Romans had revived the requirement that everyone worship the emperor as a living god. Thus, the book of Revelation is assumed to have been written at about that time. Its main theme is to call for Christian solidarity to resist the demands of the empire and to refuse to worship the emperor. The author of Revelation clearly anticipated the end of the world within a few years of the writing of the book. Of course, it never happened.
Most liberals pay little attention to the book.
They largely reject it because it portrays a God who is extremely hateful and bent on revenge against virtually all humanity. The God of Revelation bears no resemblance to the loving, kind Abba who was worshiped by Jesus. The book describes armies fighting on horseback with primitive, first century weapons. It obviously has little relevance to us today. It was simply probably apocalyptic literature which was written to bolster the morale of 1st century Christians in 7 churches, located in present-day Turkey.