Even if we leave the Avesta. entirely out of account we are still The AchlBmenian able to draw from other sources material for a study
Religion accord-of the ancient Irania.n religion. First and foremost ing to the old Persian Inscrip-we can attempt to sketch a picture of the religion tions. of the Achremenids on the basis of the old Persian
inscriptions which have been preserved. This can be furl,her supple. mented through the use of the material which is furnished in inscriptions which these monarchs caused to be written in non·Iranian languages. In the third place, numerous conclusions can be drawn from the informa· tion concerning the Achremenids to be found in classical writers, although evidence of this nature can possess only the value that is to be assigned to the statements of foreign writers. Fourthly, it is further possible to derive suggestions with rderence to thp religion of the later Achremenids from isolated passages in the Pahlavi literature or in the Shahnama. And finally additional Oriental and ot·her sources may be drawn upon to supplement these.