The name generally given to Upper Egypt (the Thebaid of the Greeks), as distinguished from Matsor, or Lower Egypt (Isa. 11:11; Jer. 44:1, 15; Ezek. 30:14), the two forming Mizraim. After the destruction of Jerusalem by Nebuchadnezzar, colonies of Jews settled “in the country of Pathros” and other parts of Egypt.
Dictionary entry
Pathros
Easton's Bible Dictionary