Proto-Arabic, or Ancient North Arabian, texts give a clearer picture of the Arabs' emergence. The earliest are written in variants of epigraphic south Arabian musnad script, including the 8th century BCE Hasaean inscriptions of eastern Saudi Arabia, the 6th century BCE Lihyanite texts of southeastern Saudi Arabia and the Thamudic texts found throughout the Arabian Peninsula and Sinai (not in reality connected with Thamud).  The Nabataeans were nomadic who moved into territory vacated by the Edomites - Semites who settled the region centuries before them. Their early inscriptions were in Aramaic, but gradually switched to Arabic, and since they had writing, it was they who made the first inscriptions in Arabic. The Nabataean alphabet was adopted by Arabs to the south, and evolved into modern Arabic script around the 4th century. This is attested by Safaitic inscriptions (beginning in the 1st century BCE) and the many Arabic personal names in Nabataean inscriptions. From about the 2nd century BCE, a few inscriptions from Qaryat al-Faw reveal a dialect no longer considered proto-Arabic, but pre-classical Arabic. Five Syriac inscriptions mentioning Arabs have been found at Sumatar Harabesi, one of which dates to the 2nd century CE.  Arabs arrived in the Palmyra in the late first millennium BCE. The soldiers of the sheikh Zabdibel, who aided the Seleucids in the battle of Raphia (217 BCE), were described as Arabs; Zabdibel and his men were not actually identified as Palmyrenes in the texts, but the name "Zabdibel" is a Palmyrene name leading to the conclusion that the sheikh hailed from Palmyra. Palmyra was conquered by the Rashidun Caliphate after its 634 capture by the Arab general Khalid ibn al-Walid, who took the city on his way to Damascus; an 18-day march by his army through the Syrian Desert from Mesopotamia. By then Palmyra was limited to the Diocletian camp. After the conquest, the city became part of Homs Province.  Palmyra prospered as part of the Umayyad Caliphate, and its population grew. It was a key stop on the East-West trade route, with a large souq (Arabic: suwq, market), built by the Umayyads, who also commissioned part of the Temple of Bel as a mosque. During this period, Palmyra was a stronghold of the Banu Kalb tribe. After being defeated by Marwan II during a civil war in the caliphate, Umayyad contender Sulayman ibn Hisham fled to the Banu Kalb in Palmyra, but eventually pledged allegiance to Marwan in 744; Palmyra continued to oppose Marwan until the surrender of the Banu Kalb leader al-Abrash al-Kalbi in 745. That year, Marwan ordered the city's walls demolished. In 750 a revolt, led by Majza'a ibn al-Kawthar and Umayyad pretender Abu Muhammad al-Sufyani, against the new Abbasid Caliphate swept across Syria; the tribes in Palmyra supported the rebels. After his defeat Abu Muhammad took refuge in the city, which withstood an Abbasid assault long enough to allow him to escape.

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