separate maps of the boundary. A number of discrepancies were noted between the maps, and five years later, in 1869, a joint map was produced which was known as the Carte identique. Despite the availability of the Carte identique and numerous discussions, Iran and Turkey continued to have disagreements on the exact alignment of their boundary.
An Anglo - Russian Convention in 1907 made a de facto division of Iran with Russia in control in the north, the United Kingdom in control in the south, and a neutral zone between the spheres of influence. In an effort to stabilize the boundary, the United Kingdom and Russia urged Iran and Turkey to agree to a detailed delimitation of their boundary. On December 21, 1911, an Irano - Turkish agreement provided for a technical commission to demarcate the boundary based on the Erzurum Treaty of 1847.
The so-called Constantinople Protocol of November 17, 1913,1 delimited the entire boundary in detail and provided again for a commission to demarcate the land boundary. The protocol stated that the Shatt al Arab was under Turkish sovereignty with the exception of certain islands and delimited the boundary in the river as follows:
[From a point between the Nahr - Diaiji and the Nahr - Abu'l-Arabid, the boundary] shall follow the medium filum aquae of the Khaiyin canal as far as the point where the latter joins the Shatt al-Arab, at the mouth of the Nahr - Nazaileh. From this point the frontier shall follow the course of the Shatt al-Arab as far as the sea, leaving under Ottoman sovereignty the river and the islands therein, subject to the following conditions and exceptions:
The following shall belong to Persia:
(1) the island of Muhalla and the two
islands situated between the latter and the left bank of the Shatt al-Arab (Persian bank of Abadan); (2) the four islands between Shetait and Maawiyeh and the two islands opposite Mankuhi which are both dependencies of the island of Abadan; (3) any small islands now existing or that may be formed which are connected at low
water with the island of Abadan or with Persian terra firma below Nahr–Nazaileh.
The modern port and anchorage of Muhammara, above and below the
junction of the river Karun with the Shatt al-Arab, shall remain within Persian jurisdiction in conformity with the Treaty of Erzerum; the Ottoman right of usage of this part of the river shall not, however, be affected thereby, nor shall Persian
jurisdiction extend to the parts of the river outside the anchorage.
No change shall be made in the existing rights, usages and customs as
regards fishing on the Persian bank of the Shatt al-Arab, the word "bank" including
also the lands connected with the coast at low water.
The delimitation and the subsequent demarcation completed in October 1914 included the boundary between Iran and what would be the present-day territories of both Iraq and Turkey.