Though some fragments on papyrus are much older, the largest number of papyri are written in Aramaic, the lingua franca of the Achaemenid Empire, and document the Jewish community among soldiers stationed at Elephantine under Achaemenid rule, 495–399 BCE. The Elephantine documents include letters and legal contracts from family and other archives: divorce documents, the manumission of slaves, and other business, and are a valuable source of knowledge about law, society, religion, language and onomastics, the sometimes surprisingly revealing study of names.