In the period of its greatest expansion, in the tenth century, the Syrian Orthodox Church had around 20 metropolitan dioceses and a little over a hundred suffragan dioceses. By the seventeenth century only 20 dioceses remained, reduced in the twentieth century to 10. The seat of Syrian Orthodox Patriarch was at Mardin before the First World War, and thereafter in Deir Zaʿfaran, Mosul, from 1932 in Homs, and finally from 1959 in Damascus.