Old Aramaic refers to the earliest stage of the Aramaic language, known from the Aramaic inscriptions discovered since the 19th century. Emerging as the language of the city-states of the Arameans in the Levant in the Early Iron Age, Old Aramaic was adopted as a lingua franca, and in this role was inherited for official use by the Achaemenid Empire during classical antiquity. After the fall of the Achaemenid Empire, local vernaculars became increasingly prominent, fanning the divergence of an Aramaic dialect continuum and the development of differing written standards.