"It has long been realized that the Marduk epic, for all its local coloring and probable elaboration by the Babylonian theologians, reflects in substance older Sumerian material," American Assyriologist E. A. Speiser remarked in 1942[14] adding "The exact Sumerian prototype, however, has not turned up so far." Without corroboration in surviving texts, this surmise that the Babylonian version of the story is based upon a modified version of an older epic, in which Enlil, not Marduk, was the god who slew Tiamat,[15] is more recently dismissed as "distinctly improbable",[16] in fact, Marduk has no precise Sumerian prototype. It is generally accepted amongst modern Assyriologists that the Enûma Elish - the Babylonian creation epic to which this mythological strand is attributed - has been written as political and religious propaganda rather than reflecting a Sumerian tradition; the dating of the epic is not completely clear, but judging from the mythological topics covered and the cuneiform versions discovered thus far, it is likely to date it to the 15th century BCE.