Rev. 2: 13I know thy works, and where thou dwellest, even where Satan’s seat is: and thou holdest fast my name, and hast not denied my faith, even in those days wherein Antipas was my faithful martyr, who was slain among you, where Satan dwelleth.
During this time the Apostles of the First Church had to deal with many affliction from Anti-Christ type Theologies. Here Christ is explaining to the Church at Pergamos that he knows where Satan’s Seat is. So what is in Pergamos?
A quick Google search turns up this Article
From reading this article we can clearly see the Church was battling Pagan Sun worship on all fronts. Just as we are Today.
There in Pergamon is The Temple of Zeus. http://www.biblicalarchaeology.org/daily/biblical-sites-places/biblical-archaeology-sites/pergamon-2/