What this song renders
By 270 AD Zenobia was already the dominant power across Roman Syria — Antioch, the Phoenician coast, and parts of Asia Minor were under Palmyrene control. The strike south into Egypt was the most audacious move of her reign. Her general Zabdas led an army (estimated at 70,000 by the sources, almost certainly inflated) down through the Sinai. Egypt was Rome's grain supply: take it and you starve Roman patronage politics.
The Roman prefect of Egypt, Tenagino Probus, was caught off-guard. He fled south, was tracked down, and died — sources differ on whether by suicide or in combat. Alexandria opened her gates by autumn 270. The clearest evidence is administrative: Egyptian papyri shift their dating formulas to acknowledge Zenobia's reign during this season, then later shift back when Rome reconquers.
The track renders the moment in the harbour at the end of the day — Zenobia standing where the Ptolemies and Caesars had stood, and realising there was no ceiling. Within a year she would drop the political fiction of acting in her son's name and declare herself Augusta.
The Egyptian campaign is documented across multiple kinds of evidence: narrative sources, papyri, and coinage. Zabdas as her named general is real. Tenagino Probus dying during the campaign is in Zosimus and corroborated by Egyptian records. The dramatised harbour-at-sunset moment is the album's; the historical fact of the conquest is solid.