John of Gischala in the context of "First Jewish-Roman War"

The siege of Jerusalem in 70 CE was the decisive event of the First Jewish Revolt against the Roman Empire (66–73 CE). Roman forces led by Titus besieged the Jewish capital, the revolt's main stronghold. After months of fighting, they breached the defenses, destroyed the Second Temple, and razed the city, killing, enslaving, or displacing much of its population. The city's fall marked the effective end of the revolt and had far-reaching political, religious, and cultural consequences.

In winter 69/70 CE, after a succession war in Rome, Titus led at least 48,000 troops—including four legions and auxiliary forces—back into Judaea. By spring, this army had encircled Jerusalem, the population of which had surged with refugees and Passover pilgrims. Inside the city, rival factions led by John of Gischala, Simon bar Giora and Eleazar ben Simon fought each other, destroying food supplies and weakening defenses. Although the factions eventually united and mounted fierce resistance, Roman forces breached the city walls and pushed the defenders into the temple precincts.

Eleazar ben Simon (Hebrew: אלעזר בן שמעון) was a Zealot leader during the First Jewish-Roman War who fought against the armies of Cestius Gallus, Vespasian, and Titus Flavius. From the onset of the war in 66 CE until the destruction of the temple in 70 CE, he fought vehemently against the Roman garrisons in Judea and against his fellow Jewish political opponents in order to establish an independent Jewish state at Jerusalem. Although the Jewish defeat at Jerusalem cannot be entirely attributed to Eleazar ben Simon, his inability to establish unity with John of Gischala and Simon bar Giora resulted in a bitter civil war that weakened the Jewish resistance against Rome. Eleazar ben Simon and his Zealots' radical anti-Roman policies and eradication of the moderate temple aristocracy from Jerusalem in 67 CE also prevented any peaceful agreement with Rome to avoid the death and destruction which ensued in 70 CE.