Arbāyistān (Parthian: 𐭀𐭓𐭁𐭉𐭎𐭈𐭍 [ʾrb]ystn; Middle Persian: Arwāstān; Armenian: Arvastan)[1] or Beth Arabaye (Syriac: Bēṯ ʿArbāyē) was a Sasanian province in Late Antiquity.

Due to its situation and its road systems, the province was a source of income from commercial traffic, as well as a constant area of contention during the Roman–Persian Wars.

In the 360s, Shapur II divided the office of marzban between his brothers Zamasp and Adurfrazgird and they were granted responsibility for the northern and southern halves of the province respectively.

[15] At the close of the fourth century, in 395, the Huns breached the Caspian Gates and swarmed through the east, plundering Armenia and Eastern Roman Cappadocia, Cilicia and Syria undisturbed until moving to raid Sasanian Arbayistan in 398.

[19] Three years into the reign of Kavad I (r. 488–496, 498/9–531), in 491, an uprising in Armenia encouraged the Qadishaye tribesmen south of Singara to revolt and besiege Nisibis.

In the spring of 504, the Roman general Celer invaded Arbayistan and conducted raids against fortified settlements, seizing several forts and plundering the province, killing farmers and livestock alike.

[23] Libelarius, however, refrained from engaging the Sasanians or looting and despite facing no opposition,[24] withdrew to Dara with heavy losses having achieved nothing, and upon his return was replaced as magister militum per orientum by Belisarius.

John was arrested and held in Nisibis for 30 days under the accusation of living in Sasanian territory illegally and was handed over to the Romans at the border fortress of Dara.

At the beginning of the Byzantine–Sasanian War of 572–591, in late 572, a small Byzantine army of 3000 infantrymen were dispatched by Marcian, magister militum per orientum, to Arzanene where they laid waste and plundered the region before returning to Dara.

[31] At the end of the war, Corduene, Aghdzen canton and Zabdicene was annexed by the Byzantine Empire in return for assisting Khosrow II regain the throne from the usurper, Bahram Chobin.

The ensuing food shortages and famine caused many to migrate to neighbouring regions, whilst those less able were forced to resort to begging in nearby cities.

The silk trade, which supplied the weaving industry of Syria, was especially lucrative and continued to thrive despite the threat of Arab raids along the roads.

[34] The Sasanian control of the two major East-West highways and excellent road system made the province easily accessible for trade.

The population of Arbayistan was primarily composed of Arameans, who spoke the Aramaic language, and shared the province with Arabs, such as the Tanukhids,[35] Jews, Armenians and Iranian peoples.