[1] Until very recently, the whole of Eastern Arabia, from the Shatt al-Arab to the mountains of Oman, was a place where people moved around, settled and married unconcerned by national borders.

[9] "Khaleeji" has evolved into a socio-political regional identity that distinguished the GCC inhabitants of the Arabian Peninsula from the wider Arab world building on the perceived cultural homogeneity within the Gulf states and their shared history.

[11] Maritime-focused life in the small Gulf Arab states has resulted in a sea-oriented society where livelihoods have traditionally been earned in marine industries.

[21] The Kingdom of Dilmun first appears in Sumerian cuneiform clay tablets dated to the end of fourth millennium BC, found in the temple of goddess Inanna, in the city of Uruk.

[25] Dilmun was also mentioned in two letters, recovered from Nippur, which were dated to the reign of Burna-Buriash II (c. 1370 BC), a king of the Kassite dynasty of Babylon.

The “Arabian Gulf” types of circular, stamped (rather than rolled) seals known from Dilmun appear at Lothal in Gujarat, India, as well as in Mesopotamia.

Mesopotamian trade documents, lists of goods, and official inscriptions mentioning Meluhha supplement Harappan seals and archaeological finds.

Enki says to Ninhursag: For Dilmun, the land of my lady's heart, I will create long waterways, rivers and canals, whereby water will flow to quench the thirst of all beings and bring abundance to all that lives.

More accurately, the ancient city of Gerrha has been determined to have existed near or under the present fort of Uqair, 80 kilometres (50 mi) northeast of Al-Aḥsā in the Eastern Province of Saudi Arabia.

[citation needed] Gerrha and Uqair are archaeological sites on the eastern coast of the Arabian Peninsula, only 100 kilometres (60 miles) from the ancient burial grounds of Dilmun on the island of Bahrain.

The researcher Abdulkhaliq Al Janbi argued in his book[38] that Gerrha was most likely the ancient city of Hajar, located in modern-day Al-Ahsa, Saudi Arabia.

[27]: 119  The Greek admiral Nearchus is believed to have been the first of Alexander's commanders to visit the island, and he found a verdant land that was part of a wide trading network.

He recorded: “In the island of Tylos, situated in the Persian Gulf, are large plantations of cotton trees, from which are manufactured clothes called sindones, of different degrees of value, some being costly, others less expensive.

The use of these is mostly confined to India, but extends also to Arabia.”[41] The Greek historian, Theophrastus, states that much of the archipelago was covered in these cotton trees and noted that textiles were a major industry.

These people, who had formerly dwelt in the far east and then to the shores of the Erythraean Sea, having migrated to the Mediterranean and settled in the parts which they now inhabit, began at once, they say, to adventure on long voyages, freighting their vessels with the wares of Egypt and Assyria...With the waning of Seleucid Greek power, Tylos was incorporated into Characene, the state founded by Hyspaosines in 127 BC in modern-day Kuwait .

[55] Ardashir, the first ruler of the Sasanian dynasty, conquered Bahrain and northern Oman, and appointed his son, Shapur I, as the governor of eastern Arabia, the province of Mazun.

[27][page needed] Mazun stretched from Oman in the south to the Shatt al-Arab in the north, and included the archipelago of Bahrain; thus it is roughly coterminous with the modern definition of Eastern Arabia.

Hafit {Tuwwam} abounds in palm trees; it lies in the direction of Hajar {Al-Aḥsā}, and the mosque is in the markets ... Dibba and Julfar, both in the direction of the Hajar, are close to the sea ... Tuwwam has been dominated by a branch of the Quraysh ...From the time when Islam emerged in the 7th century until the early 16th century, the term Bahrain referred to the wider historical region of eastern Arabia stretching from Bubiyan Island to the Strait of Hormuz along the coast of the Persian Gulf.

The expansion of Islam did not affect eastern Arabia's reliance on trade, and its prosperity continued to be dependent on markets in India and Mesopotamia.

After Baghdad emerged as the seat of the caliph in 750 following the Abbasid Revolution, eastern Arabia greatly benefited from the city's increased demand for foreign goods, especially from China and South Asia.

At the end of the 3rd Hijri century, Abu Sa'id al-Jannabi led the Qarmatian Revolution, a rebellion by a messianic Ismaili sect originating in Kufa in present-day Iraq.

The Qarmatians were organized as an esoteric society but not as a secret one; their activities were public and openly propagated, but new members had to undergo an initiation ceremony involving seven stages.

[67] They were the remnants of Bani Abdul Qays tribe and seized the country from the Qarmatians with the military assistance of Great Seljuq Empire in 1077-1078 AD.

However, the Hormuzi rulers did not seem to have firm control of the islands, and during the 14th century Bahrain was disputed as numerous neighbours sought tribute from the wealth accumulated from its pearl fisheries.

[72] The Jarwanids came to power some time in the 14th century, after expelling the forces of Sa'eed ibn Mughamis, the chief of the Muntafiq tribe based in the Iraqi city of Basrah.

Ajwad's elder brother had earlier established the dynasty in the early 15th century by deposing and killing the last Jarwanid ruler in Qatif.

At their height, the Jabrids controlled the entire Arabian coast on the Persian Gulf, including the islands of Bahrain, and regularly led expeditions into central Arabia and Oman.

[citation needed] The main branches of the Bani Khalid are the Humaid, the Jubur, the Du'um, the Janah, the Grusha, the Musallam, the 'Amayer, the Subaih and the Mahashir.

[80] Under Barrak ibn Ghurayr of the Humaid, the Bani Khalid were able to expel Ottoman forces from the cities and towns in 1670 and proclaim their rule over the region.

The Bani Khalid maintained ties with members of their tribe who had settled in Najd during their earlier migration eastwards, and also cultivated clients among the rulers of the Najdi towns, such as Al Mu'ammar of Al-Uyayna.