According to tradition, in ca. 1200 BCE, the Petra area (but not necessarily the site itself) was populated by Edomites and the area was known as Edom ("red"). Before the Israelite incursions, the Edomites controlled the trade routes from Arabia in the south to Damascus in the north. Little is known about the Edomites at Petra itself, but as a people they were known for their wisdom, their writing, their textile industry, the excellence and fineness of their ceramics, and their skilled metal working.
The next chapter of history belongs to the Persian period, and it is posited that during this time the Nabataeans migrated into Edom, forcing the Edomites to move into southern Palestine. But little is known about Petra proper until about 312 BC by which time the Nabataeans, one of many Arab tribes, occupied it and made it the capital of their kingdom. At this time, during the Hellenistic rule of the Seleucids, and later, the Ptolemies, the whole area flourished with increased trade and the establishment of new towns such as Philadelphia (Rabbath 'Ammon, modern Amman) and Gerasa (modern Jerash). Infighting between the Seleucids and Ptolemies allowed the Nabataeans to gain control over the caravan routes between Arabia and Syria. Although there were struggles between the Jewish Maccabeans and the Seleucid overlords, Nabataean trade continued.
Bibliography Finding the Lost Cities- Rebecca Stefoff published by Oxford University press Inc. © 1997
The Story of Archaeology in 50 Great Discoveries- Justin Pollard published in Quercus Great Britain 2007
Today history the discovery of Petra 24.2.14 http://www.historytoday.com/richard-cavendish/discovery-petra
‘Lost city’ of Petra still has secrets to reveal national