The collection's letters, administrative records, and military documents are significant for the linguistic study of the Official Aramaic language and of daily life in the Achaemenid empire.

The Achaemenid Empire, established in 559 BC by Cyrus the Great, covered a vast part of the Middle East, stretching from India to Africa.

[3] The Khalili documents illuminate the administration of this empire and its eventual fall to Alexander the Great in 329 BC, dealing with topics such as city fortifications, military leave, and food delivery.

[8][9] Khalili has written that he was motivated to collect Aramaic documents from the Achaemenid period because, as an Iranian Jew, he felt a personal connection to the topic.

A possibly-historical queen of the Achaemenid empire, Esther, is described in the Hebrew Bible as saving the Jewish people by dissuading her husband Ahasuerus from killing them.

[5] Khalili has described as unforgettable his experience, as a child in Iran, of hearing Aramaic, the language spoken by Moses[verification needed] and by Jesus.

[12] Khalili's collection comprises 48 documents in Official Aramaic,[7] consisting mainly of letters and accounts related to the court of the satrap of Bactria, whose capital city was Balkh.