Tiberius Julius Alexander orders his Roman legions in Alexandria to swear allegiance to Vespasian as Emperor.

AD 69 (LXIX) was a common year starting on Sunday of the Julian calendar. In the Roman Empire, it was known as the Year of the consulship of Galba and Vinius. The denomination AD 69 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Tiberius Julius Alexander was an equestrian governor and general in the Roman Empire. Born into a wealthy Jewish family of Alexandria but abandoning or neglecting the Jewish religion, he rose to become the 2nd procurator of Judea under Claudius. While Prefect of Egypt (66–69), he employed his legions against the Alexandrian Jews in a brutal response to ethnic violence, and was instrumental in the Emperor Vespasian's rise to power. In 70, he participated in the Siege of Jerusalem as Titus' second-in-command. He became the most powerful Jew of his age, and is ranked as one of the most prominent Jews in military history.

The Roman legion was the largest military unit of the Roman army, composed of Roman citizens serving as legionaries. During the Roman Republic the manipular legion comprised 4,200 infantry and 300 cavalry. In late Republican times the legions were formed of 5,200 men and were restructured around 10 cohorts, the first cohort being double strength. This structure persisted throughout the Principate and middle Empire, before further changes in the fourth century resulted in new formations of around 1,000 men.

Alexandria is the second largest city in Egypt and the largest city on the Mediterranean coast. It lies at the western edge of the Nile River Delta. Founded in 331 BC by Alexander the Great, Alexandria grew rapidly and became a major centre of Hellenic civilisation, eventually replacing Memphis, in present-day Greater Cairo, as Egypt's capital. Called the "Bride of the Mediterranean" and "Pearl of the Mediterranean Coast" internationally, Alexandria is a popular tourist destination and an important industrial centre due to its natural gas and oil pipelines from Suez.