MOSUL, a vilayet, one of the divisions into which Mesopo tamia was divided under Turkish rule, corresponds roughly to ancient Assyria. The vilayet which included the sanjaks of Mosul, Shehrizor and Sulaimaniya had an area of about 29,000 sq.m., although the actual area in dispute between Turkey and 'Iraq, and finally included in the kingdom of 'Iraq in 1926 has an area of over 35,00o sq.m. The vilayet lies mostly on the eastern bank of the Tigris : it is separated from the Bitlis vilayet and the newly constituted Hakkiari on the north by a boundary which, with slight modifications, follows the so-called Brussels or Brant ling line which runs east from the Tigris through the Slopi and Lower Tiari country to the neighbourhood of the Gadir Pass. On the east the frontier line runs through the Persian mountains including the head-waters of the eastern tributaries of the Tigris. The western frontier is a purely artificial line through the Syrian desert ; Baghdad vilayet forms the southern boundary. The whole vilayet belongs geologically to the Zagros mountain system and is of immense importance strategically because these mountains and their northern outliers form a very necessary and almost im pregnable protective zone to Baghdad and consequently the whole kingdom of 'Iraq, which would have been seriously threatened had the vilayet remained in Turkish hands. Economically the value of Mosul is equally great. It contains vast oil resources as yet practically untapped, it forms one of the principal grain growing regions of 'Iraq, while the mountain areas produce wool, hides, gall-nuts and gum. Administratively the vilayet is now divided into the liwas of Arbil, Kirkuk, Mosul and Sulaimaniya. The population, whose exact figure is uncertain, estimates ranging from half to three-quarters of a million, is mainly Sunni Muslims. It includes Kurds, who live in valley villages for nine months in the year and migrate to the mountains of Zakho and Amadia in the summer, nomad Arabs, Christians, who constitute a very special problem (see History below), Turks, Yezedis and Jews. See Report of the Commission of the League of Nations on the Mosul Boundary (1924-25) and "The Geography of the Mosul Boundary" (Major Lloyd. Geoerabhical Journal LVTTT By the Armistice of Mudros hostilities were suspended between Great Britain and Turkey from midday Oct. 31, 1918, at which time the British had advanced to a position north of Shergat, 6o m. south of Mosul. Nevertheless on Nov. 3 General Cassels informed the Turkish authorities that he had been ordered to advance beyond the armistice line and occupy the town of Mosul. This apparent violation of the armistice terms was subsequently declared to be justified by Article 7 of the armistice which laid down that "in the case of any situation arising which might men ace the security of the Allies, the latter shall have the right to occupy all strategic points." The Turks on the other hand main
tained that no such menace existed and protested strongly against this action on the part of Great Britain. Later on, further ad vances were made by the British forces; on Sept. 3o, 1924, a pro visional frontier known as the Brussels Line was proposed by the League of Nations and accepted by both Great Britain and Turkey, pending a final settlement of the dispute. This Brussels line was at its nearest points no less than 15o m. north of the armistice frontier. It ran from the Hazil to the Khabur river, then across the mountains north of the valley of the Great Zab and then due east to the Persian frontier. Roughly speaking it runs on the crest of the mountains cut through by the three rivers named.