The Sun Language Theory was a Turkish pseudolinguistic, pseudoscientific quasi-hypothesis developed in Turkey in the 1930s that proposed that all human languages are descendants of one proto-Turkic primal language. The theory's promotion of Turks as a progenitor race led to it finding favour among Turkish ultranationalists, who used it to justify their nationalist ideology.
It claims that primal language had close phonemic resemblances to Turkish and, because of this, all other languages can be traced back to Turkic roots. According to the theory, this primal language originated among Central Asian worshippers who created it as a means to salute the omnipotence of the sun and its life-giving qualities, hence the name.