Birtha (Mesopotamia) Birtha (Mesopotamia) Birtha () was an ancient fortress on the river Tigris, which was said to have been built by Alexander the Great. It would seem, from the description of Ammianus, to have resembled a modern fortification, flanked by bastions, and with its approaches defended by out-works. Shapur II here closed his campaign in 360, and was compelled to retire with considerable loss. D'Anville and Edward Gibbon both identify Birtha as modern-day Tikrit, Iraq. The word "Birtha" in Syriac means a castle or fortress, and might be applied to many places. From the known position of Dura, it has been
Early Dynastic Period (Mesopotamia) as local exchange and production centres but do not seem to have been capitals of larger political entities. The further development of maritime trade in the Persian Gulf led to increased contacts between Lower Mesopotamia and other regions. Starting in the previous period, the area of modern-day Oman—known in ancient texts as Magan—had seen the development of the oasis settlement system. This system relied on irrigation agriculture in areas with perennial springs. Magan owed its good position in the trade network to its copper deposits. These deposits were located in the mountains, notably near Hili, where copper workshops and monumental