"I kept so much from them, like a demon, manipulating them from beyond. Another of my many regrets." ― The Pilgrim
The Pilgrim is an ancient Starborn who travels through the Unity seeking its meaning and studying it. The Spacefarer can find his notes on various parts of the Unity, from Starborn ships, to Starborn spacesuits at the Pilgrim's Rest.
The Pilgrim performed many experiments, introducing the symbols to different cultures and observing their interpretations primarily religious interpretations. One of such attempted introductions was bringing a message to Jinan Va'ruun, leading to multiple fights. Jinan dubbed him "The Unbeliever". Others include introducing the symbols to the precursors of the other two human religions accessible to the Spacefarer.
"The symbols would be re-interpreted again and again. A warrior order or a secret society would spring up. I wisited them al, greedy for what their imaginations might reveal about the true nature." ― The Pilgrim
Despite their many attempts, the Pilgrim doesn't seem to have arrived at any concrete conclusion as to who the ships belong to or who created them.