Building on his previous work on Hellenistic Interstate Political Ethics (T&T Clark, 2022) leading historian Doron Mendels presents three hundred interstate ethical rules of conduct which he has discovered within three reconstructed Hellenistic codes. These codes appear in the work of three major Hellenistic historical writers, with Mendels also adding remarks that appear in The Letter of Aristeas. Mendels has formulated these - probably originally oral - rules embedded within the historical narratives using a mixture of statements by rulers and other actors concerning interstate relationships, historical events which point to ethical behaviour of states and/or their breach, as well as related thoughts of the historians themselves regarding interstate encounters. The result is a comprehensive catalogue of ethical rules referring to behaviour on the international scene, which include not only rules but also a lexicon of moral terms borrowed from the individual ethical scenarios. The volume constitutes a significant addition to knowledge of the Hellenistic era in the 3rd-1st centuries BC, the universe against which Judaism and early Christianity operated.