Then recently as I started to explore Northern American folk traditions specifically I came across the concept again. I've found that it is related to the Pennsylvania Dutch Pow Wow tradition. The idea of the term hex for the practices and design of those circles is said to be rooted in a germanic phrase.
SourceFolk Magic: The Hex sign wrote:Unlike barn stars, which were painted directly on the sides of structures, the wooden hex signs, a term likely derived from the Pennsylvania German word “hexafoo” or “witch’s foot,” could be ported around and hung not just on barns, but anywhere. Ott marketed hex signs as objects of folk magic, ascribing specific meaning and power to the symbolism on the signs.
One website says:
sourcedutchhexsign.com wrote:
My research and personal experience tells me that, whatever the history of the hex sign, the practice has been thoroughly melded with the Christian religion. All of the pre-1990 publications I have read confirm that my grandmother's practice of empowering the design "in the name of the Father, the Son and the Holy Ghost. Amen" was shared by other practitioners.
I was taught that each design was a "painted prayer," the purpose of which was to manifest on Earth (in the physical realm) that which was asked of the Spiritual realm.
Here are some Hex Signs and their symbols:
Source