"When Caesar Augustus had raised a taxation, He assessed all the people that dwelt in the nation." Mary and Joseph go to Bethlehem, but cannot find a place at the inn. They eventually find a stable, where Jesus is born
I find it hard to believe that this is actually a traditional song; the wording is too ornate and contorted.
The details in this song are either fictional or derived from Luke 2; the birth narrative in Matthew plays no part. Of course, we should also note that the account in Luke 2 is incorrect; there is no record of this particular census, and even if there had been such a census (possible, given the available documentation, but unlikely), the Romans would not allow such a mess in a frontier province threatened with Parthian invasion. - RBW