In this paper J. Paul demonstrates that the Persian historiography from 1350 to 1450 does not propose a unique term for the designation of “pastoral nomads,” nor any systematic relation between social divisions and ways of life. An integral part of the Iranian identity, the nomads are evoked differently in different sources: the “Western” texts (Eastern Anatolia & Western Iran) are more explicit on their political and military role than the “Eastern” ones (the Timurid historiography of Khurasan and Transoxiana). Two terms are analysed, both admixing social components and military signification. The sporadic occurrences of the term sahra-nishinan are more frequent in administrative documents. Through a comparison between several successive sources the author shows that this word designates nomads, whether for their military potential or for their participation in the tax system. Close to the lashkariyan, according to this interpretation the sahra-nishinan must be regarded as “privates.” It is not sure, however, that this term designates exclusively pastoral nomads. As to the word hasham or ahsham (احشام), it contains a more clearly military component: It used to designate mainly a military escort consisting of warriors mobilised for campaigns, coming from pastoral horizons and returning to their more pacific occupations after the campaign.” It could happen that the ahsham respond to this mobilisation without great enthusiasm—as shown for instance by the case of the Aq Qoyunlu. Two observations can be inferred from the analysis of these two terms: (1) pastoral nomadism appears as a true way of life; (2) pastoral nomads and horseback fighters were considered one and the same group.