 But ethno-linguistic characteristics of the region must be studied against the long and turbulent history of the province, with its own local language "khuzi", which may have been of Elamite origin and which gradually disappeared in the early medieval period.The immigration of Arab tribes from outside the province was also a long-term process.There was a great influx of Arab-speaking immigrants into the province from the 16th to the 19th century, including the migration of the Banu Kaab and Banu Lam.