Paulicianism

Paulicianism was a 7th century pre-protestant sect founded by the lay-preacher, Constantine-Silvanus, in Byzantine Armenia. Adherents called themselves Good Christians but were eventually labelled heretical by Byzantine authorities, resulting in a fierce and severe persecution.
Paulicians were accused of being dualists, satanists and iconoclasts by Byzantine Catholic authorities as well as being branded as Jews, Manicheans and later Muslims. What is known of their actual theology can be found in the Paulician treatise known as The Key of Truth, which speaks against icons, infant baptism and the established Byzantine Church. The book's teachings have been compared to modern Baptist theology.
The Paulicians are included in the line of Baptist Churches within the pseudo-historical Landmarkist conspiracy theory.