Phirmism was a religious group that utilized the Force, and it existed across the galaxy. A prominent Phirmist was Guch Ydroma; he asserted that the Phirmist deity had interacted with him during a pilgrimage through a desert on Jedha, which supposedly granted him the power to create water from the air. Another Phirmist, named Marn, managed an orphanage located at the Phirmist temple found on Durkteel. Notably, she provided shelter for Mattis Banz, a young Force-sensitive individual who later became a member of the Resistance opposing the First Order.
Ben Acker and Ben Blacker created the Phirmists for their Join the Resistance project. Blacker mentioned in an interview that the organization's name was inspired by their friend, Mike Phirman, a comedian and musician, making it one of several instances where they included tuckerizations of their friends within the book.