The Great Scroll and the Gods
Sages and theologians are at a loss to explain where the Great Scroll exists, but its existence is accepted by all the major religions. The Great Scroll is to the multiverse of Montporte what DNA is to life on earth. All the planes of the Montporte multiverse are under the influence of the Great Scroll. The life and death of every mortal creature is spelled out the Great Scroll.
The Great Scroll is a dynamic document...new words are always being added. The gods vie for the control of this writing, each seeking to sway the unknown hand that pens each word. The gods are transcendent and cannot intervene directly in the affairs of mortals but, through the Great Scroll, the gods can determine the course of existence for every living creature in the world of Montporte.
Once a word is written into the text of the Great Scroll it cannot be erased (except in a limited way by demons). However, the meaning of the older portions of the Great Scroll can be influenced, adjusted and even twisted by subsequent passages. In this way, the gods battle with each other for control of the universe.
The Great Scroll, Dragons, Demons, Fey, and Aberrations
While only gods can create the text of the Great Scroll, creatures from other planes have the ability to connect to it and shape it in one fashion or another.
Dragons, the great creatures of the plane of Zaj, are believed to have some insight and knowledge of the portions of the Great Scroll. Sages believe that the dragons ability comprehend significant portions of the Great Scroll is connected with the dragons' great thirst for knowledge, the only draconic urge stronger than their lust for treasure.
Demons are known to be able to blot out small portions of the Great Scroll text when they slay a mortal creature. The demons do not truly erase the the text of the Great Scroll, but they are somehow able to disconnect a small portion of the text related to their victim. The victim's mind, body and soul are consumed in the process by the demon.
The fey have little direct influence on the Great Scroll. However, through some ancient magic that is lost to the sands of time, the Seelie Accords (the overarching constitution and laws of the fey) are linked to the Great Scroll. While the fey draw power from the Seelie Accords, others who sign its pages put themselves at risk even as they typically find themselves materially enriched by their relationship with the fey.
Some powerful aberrations from Ioucura (the plane of Madness) have the ability to garble a word or two of the Great Scroll, usually rendering a mortal insane in the process.
The Great Scroll and the Religions of Mortals
Religion is primarily the domain of the mortals of the plane of Aarde (the material world of Montporte). Aberrations, demons, dragons and fey are certainly aware of the gods and their divine power, but worship of the gods among these creatures is rare. It is among the mortals of the plane of Aarde that the gods have their power. The symbiotic relationship between the gods and their believers empower both parties to do what would otherwise be beyond their reach.
Not every race of Aarde is equally religious. Dwarves and orcs are universally religious (albeit in very different ways). Elves are rarely so, trusting in the power of magic instead. Gnome and hobbits both exhibit a quiet faith that is manifest in small daily rituals and silent prayer.
It is among the great population of humans that the gods draw their greatest power. Within the vast sea of humanity there can be found wild-eyed true believers, faithful followers, questioning seekers, militant scoffers, and the completely indifferent. The gods of the humans have benefited by the dominance of the human race over much of Aarde. And the humans, in term, are continue to dominate because their gods hold sway over the Great Scroll.
Through religion, gods seek to draw upon the power of their followers to impose their will on the universe and move the great unhanded quill to ink the next passage on the Great Scroll. Religious followers seek to empower themselves to empower their gods and see their the fruits of their own faith as the Great Scroll shapes the course of daily events.