The era of pre-Islamic Arabia encompasses human history in all parts of the Arabian Peninsula before the rise of Islam. During the prehistoric period, humans first migrate and settle into the peninsula. In the early first millennium BC, writing and recorded history are introduced into the Peninsula, along with the rise of the first kingdoms in the south. In the early seventh century, the pre-Islamic period quickly comes to a close, from the beginning of Muhammad's preachings of Islam, to his establishment of the first Islamic state in 622 in Medina, and the subsequent conquest and political unification of the peninsula shortly after Muhammad's death, in the 630s. Some strands of Islamic tradition interpret the pre-Islamic period as a barbaric, morally un-enlightened period known as the "Jahiliyyah" (Arabic: جَاهِلِيَّة), but historians have not adopted this convention. Pre-Islamic Arabia's demographics included both nomadic and settled populations, the latter of which eventually developed into distinctive civilizations. Eastern Arabia was home to the region's earliest civilizations, such as Dilmun, which is attested as a prominent trade partner of Mesopotamia during the Bronze Age; and its later pre-Islamic history is marked by the reign of consecutive Iranian empires, including those of the Parthians and the Sasanians. From the early 1st millennium BCE onward, South Arabia became home to a number of kingdoms, such as Sheba and Ma'in; while part of North Arabia became home to the Nabataean Kingdom, which was conquered and annexed by the Roman Empire in 106, becoming the province Roman Arabia, and starting a period of Roman influence. Arabian tribes and the southern kingdoms structured much of pre-Islamic society, and memory of these societies is filtered today through Islamic literature and pre-Islamic poetry. Pre-Islamic tribes engaged in warfare and formed alliances, and for most of history, practiced Arabian religions. Religion in pre-Islamic Arabia was diverse. Polytheism was prevalent for most of the region's history, with beliefs and practices having a common origin in ancient Semitic religion. Christianity, Judaism, and monotheism became common in the region in the fourth century, a trend driven by Christian proselytization from the Eastern Roman Empire and the Kingdom of Aksum, as well as the conversion to monotheism and Judaism by the elite of the Himyarite Kingdom. Source: Wikipedia (en)