Tiris al-Gharbiyya () was the name for the area of Western Sahara under Mauritanian control between 1975 and 1979. Background Mauritania annexed the southern third of the former Spanish colony of Spanish Sahara in 1975 after the Madrid Accords, with Morocco taking the northern two-thirds (Saguia el-Hamra and the northern half of Río de Oro) as its Southern Provinces. Both countries claimed historical rights over the area, while the United Nations demanded that the indigenous population (Sahrawis) had a right to self-determination, and should be allowed to decide through a referendum whether the territory should join either of the neighbouring states, or be established as an independent country. The latter was the preferred option of the Polisario Front, a Sahrawi organization which turned its guerrilla forces against both countries, having until then fought Spain. Its attacks against Mauritania proved highly effective. Polisario strikes against the iron mines at Zouerate, as well as the costs of the war effort, soon brought the country to the brink of economic collapse, and produced increasing tensions in the army and government apparatus. In 1978, the one-party government of Moktar Ould Daddah was severely compromised by the failing war effort, and fell to a coup by disgruntled army officers. Mauritania then disengaged from the conflict, surrendering its claims to any part of Western Sahara, and pulling out its troops. The areas occupied by Mauritania were entered by Morocco, which has since claimed ownership over the entire territory, despite continued opposition by Polisario, and its main backer, Algeria. Mauritanian president Mohamed Khouna Ould Haidalla in 1984 proceeded to recognize the Polisario-backed Sahrawi Arab Democratic Republic (SADR) as the legitimate sovereign of the area. After his toppling in yet another military coup d'état later the same year, this position was increasingly downplayed – though never explicitly overturned – in order to appease Morocco. Borders and characteristics Western Tiris was the lower half of Río de Oro, the southern province of the former Spanish Sahara, comprising with a population of 12,897. It consisted mostly of barren desert terrain, scarcely populated except by some thousands of Sahrawi nomads, many of whom had fled towards the Algerian Tindouf Province in 1975. A few minor settlements dotted the coast, and the largest of these, Dakhla (formerly Villa Cisneros), was made the provincial capital. While some reports indicate the territory may hold important quantities of mineral resources such as iron – and