After the fall of the Armenian Kingdom in 428, Dvin became the residence of Sassanid appointed "marzpans" (governors), Byzantine "kouropalates" and later Umayyad- and Abbasid-appointed "ostikans" (governors). Under Arsacid rule, Dvin prospered as one of the most populous and wealthiest cities east of Constantinople. Its prosperity continued even after the partition of Armenia between Romans and Sassanid Persians, when it became the provincial capital of Persian Armenia, and eventually it became a target during the height of the Muslim conquests. According to Sebeos and Catholicos John V the Historian, Dvin was captured in 640 during the reign of Constans II and Catholicos Ezra. During the Arab conquest of Armenia, Dvin was captured and pillaged in 640, in the first raids. On January 6, 642 the Arabs stormed and took the city, with many deaths. Dvin became the center of the province of Arminiya, the Arabs called the city Dabil.