Yemen (South Arabia) is one of the oldest centers of civilization in the Near East.

Its relatively fertile land and adequate rainfall in a moister climate help sustain a stable population, a feature recognized by the ancient Greek geographer Ptolemy, who describes Yemen as Eudaimon Arabia (better known in its Latin translation, Arabia Felix) meaning Fortunate Arabia or Happy Arabia.

Between the eighth century BCE and the sixth century, it is dominated by six main states that rival each other, or are allied with each other and control the lucrative spice trade: Saba', Ma'īn, Qatabān, Ḥaḑramawt, Awsān, and Himyar.

Islam arrives in 630 CE, and Yemen becomes part of the Muslim realm.The centers of the Old South Arabian kingdoms of present day Yemen lie around the desert area called Ramlat al-Sab`atayn, known to medieval Arab geographers as Ṣayhad.

The southern and western Highlands and the coastal region are less influential politically.

The coastal cities are however already very important from the beginning for trade.

Apart from the territory of modern Yemen the kingdoms extend into Oman, as far as the north Arabian oasis of Dedan, to Ethiopia and even along the East African Coast to modern Tanzania.