Seleucid colonies of Latakia and Apamea and the cities under native aristocracies such as Horns, Damascus, Edessa and Palmyra. Each of the latter group was the centre of a petty state, among which that of Palmyra became formidable. This caravan city had grown up around a spring in the Syrian Desert, a natural stopping-place for trade between Seleucid and Roman Syria to the west and Parthian Mesopotamia to the east. Its isolated location in the heart of the desert put it beyond the easy reach of Roman legions and of Parthian cavalry, and its Arab politicians shrewdly exploited its strategic situation between the two great rivals, keeping the balance of power and profiting by neutrality. By playing one adversary against the other, they maintained the independence of their city as a buffer state.
Palmyrene chiefs secured safe-conducts for passing caravans from desert sheikhs; guides led those caravans through the barren region; mounted archers protected them against bedouin raids; and the city imposed heavy duty on each article of merchandise as it passed through its gates. The commodities comprised some of the necessities and many of the luxuries of the classical world. They did not differ much from those which had passed through Petra: wool, purple, silk, glassware, perfumes, aromatics, olive oil, dried figs, nuts, cheese and wine. The greater part of the Mediterranean trade with Persia, India and China was then handled by Palmyrenes. Industry and even agriculture flourished alongside commerce. The result was the growth of Palmyra into one of the richest cities of the Near East.
Gradually its mud huts were replaced by limestone houses. Wide streets were laid out, with the main one leading to the sanctuary of Bel. The streets were lined with colonnades, and the city assumed the aspect of a prosperous Greco-Roman town. It was not easy for the desert city to preserve full sovereignty in face of the growing ascendancy of the empire on its west. By the start of
