Mystery Babylon is introduced to us in Rev 17-18. Her name is Mystery, so she is hidden from public view. The text says that she is the city that rules over the kings of the earth. Mystery Babylon is, then, a secret community that rules over the governments of the earth.
Mystery Babylon is presented as a woman.
Religious and cultural systems are often presented in Scripture in the image of women. Revelation pictures the church as the bride of Christ. (This connection is explicitly defined in Eph 5:22-32.) Hosea defines Israel in terms of the bride of the Lord.
False religious systems are depicted as wicked women. In Ezekiel 16 compares Jerusalem with Samaria and Sodom as wicked women who were unfaithful to God. The parable of the woman in the basket in Zechariah 5 describes a woman called wickedness who rules from Shinar (Babylon). Revelation describes Mystery Babylon as the mother of every abomination.
Mystery Babylon is presented as the mother of all harlots and abominations of the earth.
What does this mean that she is mothers of all harlots and abominations. There are two distinct ideas here: she is mother of both harlots and also mother of abominations.
If harlotry is used as a symbol of false religious systems, then mother of all harlots means that mystery Babylon is the mother or source of all false religions and false philosophies ever created. If Mystery Babylon is the mother of all false religions, then she has existed from very ancient times to the present day.
Mystery Babylon, then, is a secret community based on false religion that rules over the governments and nations of the world. This book will, by weaving together both Biblical narrative and historical investigation together, trace the development and philosophies of Mystery Babylon from its origins to the present time. This book will also demonstrate how all of the major philosophies of the present age find their origins in Mystery Babylon.