In 1971 Iranian forces occupied the islands of Abu Musa, Tunb al Kubra (Greater Tumb), and Tunb as Sughra (Lesser Tumb), located at the mouth of the gulf between Iran and the UAE. The Iranians reasserted their historic claims to the islands, although the Iranians had been dislodged by the British in the late nineteenth century. Iran continued to occupy the islands in 1993, and its action remained a source of contention with the UAE, which claimed authority by virtue of Britain's transfer of the islands to the amirates of Sharjah and Ras al Khaymah. By late 1992, Sharjah and Iran had reached agreement with regard to Abu Musa, but Ras al Khaymah had not reached a settlement with Iran concerning Greater Tumb and Lesser Tumb.
The border between Oman and Yemen remained only partially defined, and, as of early 1993, border clashes had not occurred since 1988. Improving relations between Oman and the People's Democratic Republic of Yemen (PDRY, also seen as South Yemen)-- which was reunited with the Yemen Arab Republic (YAR, also seen as North Yemen) in 1990--offered some hope that the border would be demarcated. Earlier, the physical separation of the southeern portion of Oman from its territory on the Musandam Peninsula (Ras Musandam) was a source of friction between Oman and the various neighboring amirates that became the UAE in 1971. Differences over the disputed territory appeared to have subsided after the onset of the Iran-Iraq War in 1980.
Another point of contention in the gulf is the Bahraini claim to Az Zubarah on the northwest coast of Qatar and to Hawar and the adjacent islands forty kilometers south of Az Zubarah, claims that stem from former tribal areas and dynastic struggles. The Al Khalifa had settled at Az Zubarah before driving the Iranians out of Bahrain in the eighteenth century. The Al Thani ruling family of Qatar vigorously dispute the Al Khalifa claim to the old settlement area now in Qatari hands as well as laying claim to the Bahraini-occupied Hawar and adjacent islands, a stone's throw from the mainland of Qatar but more than twenty kilometers from Bahrain. The simmering quarrel reignited in the spring of 1986 when Qatari helicopters removed and "kidnapped" workmen constructing a Bahraini coast guard station on Fasht ad Dibal, a reef off the coast of Qatar. Through Saudi mediation, the parties reached a fragile truce, whereby the Bahrainis agreed to remove their installations. However, in 1991 the dispute flared up again after Qatar instituted proceedings to let the International Court of Justice in The Hague decide whether it had jurisdiction. (Bahrain refused the jurisdiction of the court, and as of early 1993 the dispute was unresolved.) The two countries exchanged complaints that their respective naval vessels had harassed the other's shipping in disputed waters.
Before the oil era, the gulf states made little effort to delineate their territories. Members of Arab tribes felt loyalty to their tribe or shaykh and tended to roam across the Arabian desert according to the needs of their flocks. Official boundaries meant little, and the concept of allegiance to a distinct political unit was absent. Organized authority was confined to ports and oases. The delineation of borders began with the signing of the first oil concessions in the 1930s. The national boundaries had been defined by the British, but many of these borders were never properly demarcated, leaving opportunities for contention, especially in areas of the most valuable oil deposits. Until 1971 British-led forces maintained peace and order in the gulf, and British officials arbitrated local quarrels. After the withdrawal of these forces and officials, old territorial claims and suppressed tribal animosities rose to the surface. The concept of the modern state- -introduced into the gulf region by the European powers--and the sudden importance of boundaries to define ownership of oil deposits kindled acute territorial disputes.
As one pretext for his invasion of Kuwait in 1990, Saddam Husayn revived a long-standing Iraqi claim to the whole of Kuwait based on Ottoman boundaries. Ottoman Turkey exercised a tenuous sovereignty over Kuwait in the late nineteenth century, but the area passed under British protection in 1899. In 1932 Iraq informally confirmed its border with Kuwait, which had previously been demarcated by the British. In 1961, after Kuwait's independence and the withdrawal of British troops, Iraq reasserted its claim to the amirate based on the Ottomans' having attached it to Basra Province. British troops and aircraft were rushed back to Kuwait. A Saudi-led force of 3,000 from the League of Arab States (Arab League) that supported Kuwait against Iraqi pressure soon replaced them.
Iran has often laid claim to Bahrain, based on its seventeenth-century defeat of the Portuguese and its subsequent occupation of the Bahrain archipelago. The Arab clan of the Al Khalifa, which has been the ruling family of Bahrain since the eighteenth century, in turn pushed out the Iranians in 1780. The late shah, Mohammad Reza Pahlavi, raised the Bahrain question when the British withdrew from areas east of Suez, but he dropped his demand after a 1970 UN-sponsored plebiscite showed that Bahrainis overwhelmingly preferred independence to Iranian hegemony. The religious leaders of the Iranian Revolution revived the claim to Bahrain primarily on the grounds that the majority of Bahrainis were Shia Muslims. Iranian secular leaders subsequently renounced the claim in an attempt to establish better relations with Bahrain.
A particularly long and acrimonious disagreement involved claims over the Al Buraymi Oasis, disputed since the nineteenth century among tribes from Saudi Arabia, Abu Dhabi, and Oman. Although the tribes residing in the several settlements of the oasis were from Oman and Abu Dhabi, followers of the Wahhabi religious movement that originated in Saudi Arabia had periodically occupied and exacted tribute from the area. Oil prospecting began on behalf of Saudi oil interests, and in 1952 the Saudis sent a small constabulary force to assert control of the oasis. When arbitration efforts broke down in 1955, the British dispatched the Trucial Oman Scouts to expel the Saudi contingent. After a new round of negotiations, a settlement was reached whereby Saudi Arabia recognized claims of Abu Dhabi and Oman to the oasis. In return, Abu Dhabi agreed to grant Saudi Arabia a land corridor to the gulf and a share of a disputed oil field. Other disagreements over boundaries and water rights remained, however.
In August 1991, Kuwait charged that a force of Iraqis, backed by gunboats, had attacked Bubiyan but had been repulsed and many of the invaders captured. UN investigators found that the Iraqis had come from fishing boats and had probably been scavenging for military supplies abandoned after the Persian Gulf War. Kuwait was suspected of having exaggerated the incident to underscore its need for international support against ongoing Iraqi hostility.
The boundary issue again arose when the Baath (Arab Socialist Resurrection) Party came to power in Iraq after a 1963 revolution. The new government officially recognized the independence of Kuwait and the boundaries Iraq had accepted in 1932. Iraq nevertheless reinstated its claims to Bubiyan and Warbah in 1973, massing troops at the border. During the 1980-88 war with Iran, Iraq pressed for a long-term lease to the islands in order to improve its access to the gulf and its strategic position. Although Kuwait rebuffed Iraq, relations continued to be strained by boundary issues and inconclusive negotiations over the status of the islands.
You can read more regarding this subject on the following websites:
Territorial disputes in the Persian Gulf - Wikipedia
Persian-gulf-states Country Studies index
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