The content of the letter pertains to matters related to the marriage of Tushratta's daughter, Tadukhipa, to Amenhotep III.
[1] An exception was a document whose language was initially unidentified,[2] so it was preliminarily referred to as Mitanni – from the name of the state ruled by the author of the letter.
Friedrich Delitzsch, in his Akkadian synonym list, annotated these words with su(-bir4ki), speculating that they contained a variation of the name of the land of Subartu.
[5] In 1890, Henry Sayce published the results of research on non-Semitic and non-Sumerian proper names and common words found in Akkadian texts in correspondence from Tell el-Amarna and Tunip.
[2] The Mitanni Letter was studied by scholars such as Peter Jensen, Rudolph E. Brünnow, Ludwig Messerschmidt, and Ferdinand Bork.
Peter Jensen observed that the text contained words identical to those marked with the su(-bir4ki) note from Delitzsch's list.
Ludwig Messerschmidt in 1899 and Henry Sayce a year later published analyses of one of the Akkadian documents from Tunip, dating from the Amarna period and containing foreign glosses.
In 1906, Ferdinand Bork added numerous proper names to this group, discovered in texts from Old and Middle Babylonian periods [pl].
They compared the text to other documents of Tushratta written in Akkadian and found in Tell el-Amarna alongside the Mitanni Letter.
The Mitanni Letter under the designation VAT 422 (EA 24) is housed in the Amarna collection of the Egyptian Museum of Berlin.
[9] In 1915, Otto Schroeder published the cuneiform autograph of the Mitanni Letter in his work Die Tontafeln von El-Amarna, assigning it the number 200.
[9]At the end of the 15th century BCE, Thutmose IV, seeking an ally in the Near East to support his control over Syria, established political relations with Artatama I, the ruler of Mitanni.
The letter contains matters concerning the marriage of Tadukhipa to Amenhotep III, mentions of her dowry, with references to previous letters listing items given to Tadukhipa as dowry, references to building good political relations between Egypt and Mitanni, information about the exchange of envoys along with their names – the Egyptian Mane and the Mitannian Keliya, assurances of friendship between the two states, and Mitanni's loyalty to Egypt.