Short answers, pulled from the story.
Flavius Josephus, born Yosef ben Mattityahu around AD 37, was a Roman-Jewish historian and military leader. He is best known for writing The Jewish War, and he was born in Jerusalem to a father of priestly descent and a mother who claimed Hasmonean royal ancestry.
Josephus surrendered to the Roman army led by Vespasian in AD 67 after the six-week siege of Yodfat. He claimed a divine revelation predicting Vespasian would become emperor, and after that prediction came true, Vespasian freed him in AD 69 and Josephus took the family name Flavius.
Josephus resisted the Roman siege of Yodfat, also called Jotapata, until the town fell in the lunar month of Tammuz. He said he was trapped in a cave with 40 companions, suggested collective suicide by lot, and ended as one of two survivors who surrendered to the Romans.
Josephus wrote The Jewish War, finished in AD 78, and Antiquities of the Jews, completed around AD 93 or 94. He also wrote Against Apion around AD 97 and the autobiographical Life of Josephus around AD 94 to 99.
Josephus's works are the chief source next to the Bible for the history of ancient Israel and provide an independent extra-biblical account of figures including Pontius Pilate, Herod the Great, John the Baptist, James the brother of Jesus, and Jesus of Nazareth. They also illuminate first-century Judaism and the background of early Christianity.
Josephus was widely viewed as a traitor, especially in Jewish tradition, where he remained obscure for centuries. Author Joseph Raymond called him the Jewish Benedict Arnold for betraying his troops at Jotapata, and historian Mary Smallwood described him as guilty of shocking duplicity in saving himself by the sacrifice of his companions.