This article offers a detailed interpretation of the fragmentary Akkadian solar hymn and prayer from modern Ortaköy/ancient Šapinuwa recently published by D. Schwemer and A. Süel (DAAM 2.6). As recognised by its editors, DAAM 2.6 is an intermediary version that links the Sumerian solar hymn 'Utu N' from southern Mesopotamia to the Hittite corpus of solar hymns and prayers CTH 372-374 from central Anatolia. On the basis of DAAM 2.6 and other recent Sumerological and Hittitological research, the present article seeks to reconstruct the contexts and transmission of the Sumerian, Akkadian and Hittite sources: it is here argued, in particular, that the poem is likely always to have been associated with royal cults of the Sun, in both Mesopotamia and Anatolia. DAAM 2.6 and related texts therefore deserve attention not only as a uniquely detailed example of multi-lingual literary transmission in the ancient Near East, but also as a paradigm for cultural and religious contact in the ancient world in general. The present article seeks to facilitate the interpretation of the sources by offering a commentary on those passages of the hymn and prayer that are currently extant in Sumerian, Akkadian and Hittite, with a focus on philological aspects and on the choices made by the Hittite translators of the Sumero-Akkadian model.It has long been recognised that the well-known Hittite corpus of hymns and prayers to the Sun-god CTH 372-374 was in many respects composed on the basis of Sumero-Akkadian 2 models from Mesopotamia. 1 An important new impetus arrived in 2009 with A. Cavigneaux's first edition of an Old Babylonian Sumerian solar hymn and prayer, which turned out to provide the ultimate model for two central and coherent sections of the Hittite texts, namely the opening hymn to the Sun-god and the diseased supplicant's prayer for information on the nature of the offence for which (he believes) he is being punished by his personal god. 2 In 2021 D. Schwemer and A. Süel published an Akkadian version of the solar hymn and prayer, written by a Hittite scribe and discovered in Ortaköy/Šapinuwa (DAAM 2.6), which agrees with previous conjectures that there must have existed an Akkadian intermediary between the Sumerian and Hittite texts. 3 As a result, this Sumerian-Akkadian-Hittite solar hymn and prayer now presents an unprecedented combination of textual coherence, linguistic diversity and cultural impact.The fact that Sumero-Akkadian literature was copied and sometimes translated in the wider ancient Near East is well-known and well-documented. 4 In this instance, we are in a unique 1 See Güterbock (1958), with references to earlier scholarship.-I am grateful to Prof. A. Willi for his invitation to contribute to the Comparative Philology Graduate Seminar in Oxford, in March 2022, which gave me an opportunity to read DAAM 2.6 in detail, and to the participants in that Seminar for their responses. I also thank Prof. P. Attinger, Prof. H.C. Melchert, Prof. D. Schwemer and Dr C. Steitler for their improvements on earlier versions ...