Citizenship: Sergius was an archimandrite of the convent called
that of the house of Mar Gyln, in the territory of the city of
Amida.
Sources:
E. W Brooks, trans.,Lives of the Eastern Saints II,Patrologia Orientalis 18.4 (1924), https://archive.org/stream/patrologiaorient18pariuoft#page/n521/mode/2up, p: 657.