“But thou, Beth-lehem Ephrathah, which art little to be among the thousands of Judah, out of thee shall one come forth unto Me that is to be ruler in Israel; whose goings forth are from of old, from ancient days” (Micah 5:2).
Bishop Makarios of Jerusalem built the original structure at the direction of Emperor Constantine following the First Council of Nicaea in 325.  
In 384 Jerome took up residence in Bethlehem, to be joined two years later by Paula and her daughter Eustochium. Jerome wrote there a new translation of the Old and New Testament (the Vulgate). Paula, Eustochium and Jerome were buried beneath the church beside the cave of Jesus.
The church was completely destroyed in the Samaritans Revolt of 529. The present Church of the Nativity is one of the earliest Christian structures. It was built during the reign of the Byzantine Emperor, Justinian. It was by chance that this building escaped destruction during the Persian invasion of 614CE. The destructive Persians passed it because they found the Magi in familiar dress represented in the mosaic on the façade. It was the only church in the country to be spared. 
The main access to the Basilica is by a very small door. Visitors must enter the church bending over. Originally, the church had three entrances, two of which have been blocked up. The Crusaders reshaped the central and the highest portal of the Justinian church door. The present small entrance was made during the Ottoman era to prevent mounted horsemen from entering the Basilica. 
Past the main entrance is the former narthex, and a single wooden door gives access to the interior. The panels of the door were constructed at the bidding of the Armenian king Haytoun, in 1277, and these were made by two Armenian artists. The interior of the church contains four rows of red limestone pillars. From 1130 the Crusaders decorated the upper part of the pillars with paintings of saints whose names appear in Latin and/or Greek. 
The octagonal baptismal font originally stood near the high altar of the sixth century church; the inscription reads, “For remembrance, rest, and remission of sins of those who names the Lord knows”. 
The remains of mosaic decoration on the walls of the nave date from the restoration of 1165-1169 and attributed to a “Basilus Pictor”, his name appears at the foot of the third angel from the right on the northern wall; it is written with the syllables placed one above the other. Originally all the inner walls of the church were covered with mosaics.  
Steps lead on either side of the altar down to the cave of birth. A silver star on the Altar of the Nativity marks the spot where Jesus was born. The original star placed here by the Roman church in 1717 was removed by Greeks in 1847. The Turks replaced it and this incident became a contributing factor to the outbreak of the Crimean War. The Franco-Russian dispute over the holy places in Palestine was the immediate cause of the Crimean War. France’s interest in Palestine had been stimulated by a domestic crisis of 1840-1841. Napoleon II pushed it because he relied on the support of militant clerical groups in France. In 1850 Napoleon III requested the restoration to French Catholics of the capitulations of 1740. This meant that the French wanted the key to the Church of the Nativity in the old city of Jerusalem and the right to place a silver star on Christ’s birthplace in Bethlehem.
In another corner of the grotto, three steps down, is the Chapel of the Manger where Christ was laid.
The Church of St. Catherine was built in 1881 and incorporates the remains of Crusader buildings discovered during construction.
From this church the steps lead down to a complex of caves and tombs linked to the Grotto of the Nativity. The central altar in this complex is devoted to St. Joseph, the earthly father of Christ. The Chapel of the Innocents, next to it, commemorates the babies who were slaughtered by Herod after the Holy Family had left the place.