Tengri

The oldest written attestations invoke Tengri in a cosmogonic context: the Orkhon inscriptions open with the formula, "When the blue sky [Tengri] above and the brown earth below were created...", situating Tengri at the creation of the sky and as a primary cosmic principle. Early usage generally treats the term as meaning "sky," but later developments in Turkic and Mongolic contexts personified this sky-principle into a chief god credited with creating all things. Over centuries of contact with other religions, Tengri's conceptual range expanded further to serve as a translation or analogue for monotheistic divine figures in Christian and Islamic contexts among Turkic-language speakers.

In the sources Tengri is primarily depicted as the blue sky or heaven rather than a consistent anthropomorphic figure; the Orkhon inscription wording emphasizes Tengri as sky. Some traditions and later summaries describe Tengri in familial terms—identified as father of the sun (Koyash) and moon (Ay) and associated with core beings such as the Earth Mother (Umay Ana) and other deities like Erlik and Ülgen—but the cited material does not provide a standard humanlike visual description.

Across the documented tradition Tengri functions as sovereign controller of the celestial sphere, a source of life and fate, and the judge whose will shapes human affairs. In steppe political theology Göktürk khans justified their authority by claiming a mandate (kut) received from Tengri and were often described as Tengri's sons or representatives on earth. Mongolian formulations record that Tengri's will can intervene in exceptional cases by sending a chosen person to earth. Later linguistic and religious contact resulted in Tengri's name being used to refer to monotheistic divine figures in Turkic Christian and Islamic usage, showing functional flexibility.