When was Jesus born?
Jesus was born when Herod was king in Judea and when Caesar Augustus ruled the Roman Empire.
Matthew 2:1 Now when Jesus was born in Bethlehem of Judaea in the days of Herod the king, behold, there came wise men from the east to Jerusalem
Luke 2:1 And it came to pass in those days, that there went out a decree from Caesar Augustus, that all the world should be taxed. 2 (And this taxing was first made when Cyrenius was governor of Syria.) 3 And all went to be taxed, every one into his own city. 4 And Joseph also went up from Galilee, out of the city of Nazareth, into Judaea, unto the city of David, which is called Bethlehem; (because he was of the house and lineage of David:) 5 To be taxed with Mary his espoused wife, being great with child.
Herod I, or Herod the Great, was the king of Judea c.37 – 4 BC ruling as a client of Rome. Caesar Augustus was the first Roman emperor, reigning from 27 BC until his death in AD 14. Jesus is generally believed to have been born between 6 and 4 BC. He was certainly not born on December 25th.
Luke gives us more information some 30 years later when John Baptist began his ministry.
Luke 3:1 Now in the fifteenth year of the reign of Tiberius Caesar, Pontius Pilate being governor of Judaea, and Herod being tetrarch of Galilee, and his brother Philip tetrarch of Ituraea and of the region of Trachonitis, and Lysanias the tetrarch of Abilene, 2 Annas and Caiaphas being the high priests, the word of God came unto John the son of Zacharias in the wilderness.
Tiberius Caesar reigned 14 AD –37 AD.
Pontius Pilate was the Roman prefect of Judea between 26 and 36 AD.
Herod Antipas reigned: 4 BC – 39 AD
Philip was tetrarch of Ituraea from 4 BC – 34 AD
We cannot determine the exact date of Jesus birth, but 6-4BC is about right.
I hope you find this helpful.