She was originally worshiped across Upper Mesopotamia as a healing goddess, but later on came to be secondarily viewed as a male messenger god in Babylonia.
Kakka's oldest attested cult center is Maškan-šarrum, located in the south of Assyria, though she was also worshiped in the kingdom of Mari, especially in Terqa.
[4] The spelling ga-ga remained in use through the entire Old Akkadian period and in later times in Babylonia and Assyria, but additional variants are attested in texts from Mari and Terqa, including gag-ga, ka-ak-ka and ka-ka.
[7] It is presumed that this role is reflected in the theophoric name ga-ga-a-zu (from asû, "healer") which has been identified in a text from Tell al-Suleimeh, an archeological site located in the proximity of the Diyala River, possibly corresponding to ancient Awal.
[7] Furthermore, in the Old Babylonian forerunner of the god list An = Anum Kakka (dga-ga) appears in sequence with the medicine goddesses Gu2-la2, Ninisina and Ninkarrak.
[11] Kakka could also function as a divine messenger, and is portrayed as a servant of Anu in the myth Nergal and Ereshkigal and Anshar in Enūma Eliš.
[16] A hymn preserved on the tablet CBS 14073 compares Ninshubur (referred to with the feminine form of her name in the Emesal dialect, Gašanšubura) to Kakka.
[17] They are also identified with each other in the god list An = Anum (tablet I, line 31), where Kakka is explained as the name of Ninshubur as "vizier of Anu, who holds the exalted staff" (sukkal an-na-ke4 gišgidru maḫ šu du8-a).
[15] Ryan D. Winters suggests that the identification between Kakka and Ninshubur might have relied on the awareness that both names could simultaneously refer to a male and a female deity.
[22] However, according to Dietz Otto Edzard, the sukkal of Ningal was most likely a distinct Gula-like medicine goddess, and the apparent association between her Kakka might be the result of confusion.
[1] Richard L. Litke argued that the gloss in the name dMEkà-kàME in An = Anum (tablet III, line 39) is unlikely to refer to an otherwise unknown reading of the sign ME, and assumes that the deity in mention was named Meme, with kà-kà being merely an indication that a possible alternate version of the list had Kakka in the same line, possibly due to both Meme and Kakka being equated with Ninkarrak elsewhere.
[8] Maškan-šarrum was regarded as a cult center of Kakka, as indicated by a tablet from Puzrish-Dagan from the reign of Amar-Sin which mentions that it was the residence of a nin-dingir priestess of this deity.
[27] Due to the association between Kakka and Maškan-šarrum it has been proposed that Šū-Kakka, a king known from a seal impression found during excavations of Eshnunna and presumed to be a contemporary of Bilalama, ruled over this city.
[1] Piotr Steinkeller argues that Kakka's presence in only one version of this myth might indicate that the assignment of a name to the god sent by Anu was an Assyrian addition.
[8] In the beginning of the composition, Kakka descends to the underworld on Anu's behalf to greet Ereshkigal and invite her to send a representative to the banquet held in heaven.
[8][b] A different explanation has been suggested by Selena Wisnom, who postulates that the passage might represent a literary allusion to the role of the personified weapon Šarur in myths about Ninurta, especially Lugal-e and the Epic of Anzû.