"And Many Went...Up To Jerusalem"
It is often asked "How many lived in Jerusalem during the time of Jesus?" But there is really no reliable sources that would indicate any population figures during the time of Jesus. The main sources available estimate a population of around 80,000 to 100,000 citizens. But hundreds of thousands of Jews from the diaspora which numbered around 4,000,000 visited Jerusalem for the Passover and other festivals yearly with an estimated 3,000,000 people, both Jews and Gentiles, visiting Jerusalem during the Passover when the Lamb of God was lifted on a Roman cross.
According to Josephus, Hecataeus of Abdera wrote in the 4th century BC that Jerusalem "is inhabited by 120,000 men." Josephus also said that there were 2,700,000 people within the walls of Jerusalem when the Romans, under Titus, beseiged it in 70 AD. Tacitus recorded Jerusalem at 600,000 men women and children. Palestine as a whole contained around 3 to 4 million inhabitants.
When the Jewish rebellion began under the emperor Nero the number of Jews increased rapidly coming from all over the world seeking protection within the high walls and fortifications of the city. Josephus records that 1,100,000 Jews perished during the seige and 97,000 were taken as captives and sold into slavery. This was about 40 years after the crucifixion of Jesus.
Rome had an estimated 1,200,000 inhabitants and considered the largest city with Alexandria placed second, and Antioch third. History records that there were around 100,000,000 people within the 1,500,000 square miles of the Roman Empire during the time of Christ.