A simple outline for the book of Revelation is found in Revelation 1:19. In the first chapter, the risen and exalted Christ is speaking to John. Christ tells John to “write, therefore, what you have seen, what is now and what will take place later.” The things John had already seen are recorded in chapter 1. The “things which are” (that were present in John's day) are recorded in chapters 2–3 (the letters to the churches). The “things that will take place” (future things) are recorded in chapters 4–22. Generally speaking, chapters 4–18 of Revelation deal with God's judgments on the people of the earth.
While the Apostle John was still alive, it was common to brand slaves or enemy soldiers, or to place the sign of the cross on the forehead of a new Christian. During the time of the Roman Empire, "the mark of the beast" apparently symbolised allegiance to the demands of the imperial cult.
Looking ahead to the end-times and to the revealing of the Antichrist, the "mark of the beast" identifies those who submit to the Antichrist, who deny Christ. Last time I looked, Catholics and Protestants alike do not deny Christ.
God's judgments on the people of the earth and the identification of the Antichrist point to the future, not the past.
Source: New International Version Study Bible notes on Revelation 13:16