Ancient kingdom, Middle East.
Occupying the area of the lower Euphrates River valley and the upper part of the Persian Gulf , it was ruled by the Lakhmids (3rd century AD–602), who themselves were subordinate to the Sāsānian dynasty of Persia. Its chief town, also named Al-Ḥīrah, was a diplomatic, political, and military centre and an important station on the Persia-Arabia caravan route. Tradition holds that the Arabic script was developed there. Also the seat of a bishopric for Nestorian Christians, it promoted Christian monotheism in the Arabian Peninsula . Al-Ḥīrah began to decline after the Sāsānians dissolved the Arab state there early in the 7th century, and in 633 the town was taken by the Muslims.