The ancient people of Assyria spoke an Assyrian dialect of the Akkadian language, a branch of the Semitic languages. The first inscriptions, called Old Assyrian (OA), were made in the Old Assyrian period. In the Neo-Assyrian period the Aramaic language became increasingly common, more so than Akkadian — this was thought to be largely due to the mass deportations undertaken by Assyrian kings, in which large Aramaic-speaking populations, conquered by the Assyrians, were relocated to other parts of the empire. The ancient Assyrians also used the Sumerian language in their literature and liturgy, although to a more limited extent in the Middle- and Neo-Assyrian periods, when Akkadian became the main literary language.

The utter and complete destruction of the Assyrian capitals of Nineveh and Assur by the Babylonians and Medes ensured that the bilingual elite, perhaps the few remaining still competent in Akkadian, were wiped out. By the 6th century B.C., much of the Assyrian population that survived used Aramaic and not the cuneiform Akkadian. In time, Akkadian would no longer be used by the Assyrians, although many aspects of the culture associated, such as naming with Assur, continued, and do so today.