Aḥdāth (lit., "young men") is usually understood to refer to urban militias of post-third/ninth century Syria and the Jazīra. The term's etymology (from ḥ-d-th , "to occur, come to pass") remains obscure.The earliest Arabic references, for Kufa and Basra exclusively, are to an office of aḥdāth in the later Umayyad and early ʿAbbāsid periods (von Sievers, 214-216). The largest number of references occurs in al-Ṭabarī's Taʾrīkh (ed. de Goeje; in the English translation, direct references are 14:16; 15:136, 189; 26: