The Ishmaelites were merchants and traders. They lived on the caravan-road which brought the spices of southern Arabia to Canaan and Egypt, and the trade was largely in their hands. In the history of Joseph we hear of them carrying the balm of Gilead and the myrrh of the south on their camels to Egypt, and in the second century before the Christian era the merchant princes of Petra made their capital one of the wealthiest of Oriental cities. It was not until 105 A.D. that the Nabathean state was conquered by Rome, and the Ishmaelites of northern Arabia transformed into Roman subjects. They have left their tombs and inscriptions among the rocks of Petra, while the cliffs of the Sinaitic Peninsula are covered with the scrawls of Nabathean travellers. Southward of the Ishmaelites came the Midianites. Midianites and Ishmaelites were alike of the same blood. Both traced their descent from Abraham; it was only on the side of the mother that their origin was different. While the Ishmaelites claimed connection with Egypt, the Midianites were more purely Arabic in race. The name of Keturah their ancestress means "incense," and points to the incense-bearing lands of the south. Midian was properly the district which stretched along the western coast of the Gulf of Aqaba towards Mecca, if not towards Yemen. But Midianite tribes had also pushed northwards and mingled with the descendants of Ishmael. "Ishmaelites" and "Midianites" seem convertible terms in the story of Joseph, and the Midianites who swarmed into the north of Israel in the days of Gideon, along with the Amalekites and "the children of the East," must have been as much Ishmaelite as Midianite in descent. Between the Midianites and the Israelitish fugitives from Egypt there had been close affinity. Moses had found a refuge in Midian, and his wife and children were Midianite in race. His father-in-law, "the priest of Midian," had visited him under the shadow of Sinai, and had given him his first lessons in political organisation. A Midianite remained to guide the Israelites through the wilderness, and the Kenites, who took part with the tribe of Judah in the conquest of Canaan, appear to have migrated from Midian. It was not until just before the invasion of Palestine that the old bonds of friendship and mixture between Israel and Midian were broken asunder. Midianite hosts had overrun the land of Moab as at a later time they overran the land of Israel, and the Israelites had forsaken Yahveh for the worship of the Midianite Baal-Peor. This was the result of intermarriage; the Israelites had taken Midianite wives and conformed to the licentious rites of a Midianite god.