What was the world population at the time of Jesus' first coming?
At Jesus' first advent, the population of the then-known world was probably fewer than 500 million—roughly half a billion. This estimate comes after about 4,000 years of human history and 2,400–2,600 years after the Flood. That number did not double to a billion until about 1860.
Les explains that at the time of Christ, at His first advent, there were probably less than 500 million people in the whole then-known world—only half a billion. He contrasts that with the present day, when there are over 5 billion people on the planet and the number is rushing toward 5.5 and 6 billion. He also notes that this 500 million did not double and become a billion until about 1860, and that it came after 4,000 years of human history and 2,400–2,600 years after the Flood.