 The invasion of Egypt is sometimes explained by Zenobia's desire to secure an alternative trade route to the Euphrates, which was cut because of the war with Persia, although the Euphrates route was only partially disrupted, and Zenobia's personal ambition and political motivation to establish Palmyrene dominance over the east definitely played a part in her decision to invade Egypt.The Palmyrenes entered Alexandria, and left a garrison of 5,000, although shortly after, Tenagino Probus, Egypt's prefect, who was occupied with naval expeditions against pirates, was alerted of the situation in Egypt and quickly returned there.He recaptured Alexandria, but the Palmyrene army shortly thereafter regained control of the city.