Contemporary information may come from archaeological excavations, pre-Islamic Arabian inscriptions, and literary accounts from observers beyond the peninsula (including by Assyrians, Babylonians, Israelites, Greeks, Romans, and Persians).

In addition, new scripts and alphabets were developed, which were of great utility to merchants for producing contracts and conducting other and related economic affairs.

Here and across the next century, Dilmun appears as a polity that is not directly ruled by Assyria, although it sends tribute to the Assyrian rulers in exchange for peace and independence.

After Alexander the Great returned from his conquests that reached India, settling in Babylonia, it is said by the historian Arrian that he was turning his attention towards an invasion of the Arabian peninsula.

Soon after the conquests of Alexander the Great, it became the most important center of trader for the Hellenistic world in the Gulf region, known for its transport of Arabian aromatics and goods from India further away.

[35] While there is no certainty as to which archaeological site the Gerrha of Greek sources can be identified with, the most prominent candidates have been Thaj and Hagar (modern-day Hofuf).

[38] The Greek admiral Nearchus is believed to have been the first of Alexander's commanders to visit this islands, and he found a verdant land that was part of a wide trading network; he recorded: "That in the island of Tylos, situated in the Persian Gulf, are large plantations of cotton tree, from which are manufactured clothes called sindones, a very different degrees of value, some being costly, others less expensive.

"[39] The Greek historian, Theophrastus, states that much of the islands were covered in these cotton trees and that Tylos was famous for exporting walking canes engraved with emblems that were customarily carried in Babylon.

[41] Tylos was integrated well into the Hellenised world: the language of the upper classes was Greek (although Aramaic was in everyday use), while Zeus was worshipped in the form of the Arabian sun-god Shams.

[43] Another important player in this time was the Parthian Empire, which emerged from northeastern Iran and relinquished a significant amount of territory from the eastern borders of the Seleucids.

Seizing the moment, Ardashir I, the first ruler of this dynasty marched down the Persian Gulf to Oman and Bahrain and defeated Sanatruq[46] (or Satiran[38]), probably the Parthian governor of Eastern Arabia.

[38][47] Sasanian interests in the region largely lay in controlling traffic through the Persian Gulf, but land-incursions into the peninsula were occasionally undertaken, such as when the inhabitants of Eastern Arabia invaded southern Iran during the reign of Shapur II in the fourth century CE.

This region encompassed a territory that, today, includes Bahrain, Tarout Island, Al-Khatt, Al-Hasa, Qatar, and possibly the United Arab Emirates.

[50] By the 5th century, Beth Qatraye was a major centre for Nestorian Christianity, which had come to dominate the southern shores of the Persian Gulf.

[63][64][65] Under the leadership of Karib'il Watar, Saba dominated most of modern-day Yemen, a feat that would not be accomplished again in the region until the Himyarite Kingdom a thousand years later.

There is some debate as to the degree to which the movement out of the formative phase was channeled by endogenous processes, or the transfer or technologies from other centers, perhaps via trade and immigration.

In the late 7th century BCE, under the reign of its ruler Murattaʿ, Awsan entered a military conflict with the Kingdom of Saba that brought about its demise.

[88] The most organized of the Northern Arabian tribes, at the height of their rule in the 6th century BCE, the Kingdom of Qedar spanned a large area between the Persian Gulf and the Sinai.

They participated in the Second Persian invasion of Greece (479-480 BCE) while also helping the Achaemenids invade Egypt by providing water skins to the troops crossing the desert.

During the following period of great prosperity, the Arab citizens of Palmyra adopted customs and modes of dress from both the Iranian Parthian world to the east and the Graeco-Roman west.

[94] The Kindites established a kingdom in Najd in central Arabia unlike the organized states of Yemen; its kings exercised an influence over a number of associated tribes more by personal prestige than by coercive settled authority.

Arabian polytheism was, according to Islamic tradition, the dominant form of religion in pre-Islamic Arabia, based on veneration of deities and spirits.

[106] The earliest evidence of Hellenistic contact in the Arabian peninsula goes back to the 3rd century BC, but at this time, it is only occurring in Eastern Arabia, as shown by the amphorae from Rhodes and Chios.

[74] At the Kingdom of Saba, the traditional Near Eastern norms of iconographic depictions of the gods give way to Roman and Hellenistic anthropomorphic styles around the turn of the Christian era.

[108] Recently, Latin inscriptions have revealed a Roman military presence as far south as the Farasan Islands, in southwestern Saudi Arabia.

[106] In Central Arabia, statues of Greek deities like Artemis, Heracles, and Harpocrates have been discovered have been found at Qaryat al-Faw, the former capital of the Kingdom of Kinda.

It left both the Byzantine and Sasanian empires exhausted and susceptible to third-party attacks, particularly from nomadic Arabs united under a newly formed religion.

The Arabian Peninsula had a long coastline for merchant ships and an area of lush vegetation known as the Fertile Crescent which could help fund his expansion into Europe and North Africa.

Justinian viewed his mercenaries as so valued for preventing conflict that he awarded their chief with the titles of patrician, phylarch, and king – the highest honours that he could bestow on anyone.

[113][need quotation to verify] By the end of the seventh century, an empire stretching from the Pyrenees Mountains in Europe to the Indus River valley in South Asia had been established.