Incense, Monotheism and the Coming of Islam

The South Arabian kingdoms were built on incense. Frankincense and myrrh grow in Dhofar and Hadramawt and almost nowhere else, and the caravan route north through the Hejaz to the Mediterranean carried them to temples across the ancient world, so that a religion in Rome or Jerusalem depended on the agriculture of southern Arabia. Nigel Groom's study reconstructs the trade in detail. The dam at Marib, one of the great engineering works of the ancient world, watered the kingdom that controlled it.

Late in the period the region turned monotheist. From the fourth century the inscriptions stop naming the old gods and begin invoking a single lord of heaven, and both Judaism and Christianity became established there. The Himyarite king known as Dhu Nuwas adopted Judaism and is associated with a massacre of Christians at Najran in the sixth century, which brought Aksumite intervention from across the Red Sea and a period of Ethiopian and then Persian rule.

That is the immediate background to Islam, and the Quran alludes both to the people of the ditch and to the collapse of the dam. Old South Arabian died out as Arabic spread. The unrelated Modern South Arabian languages, Mehri and Soqotri among them, are still spoken and are not its descendants, a point regularly confused in general accounts.