What was the first Christmas really like?

The school nativity plays are clear: Mary and Joseph arrive in Bethlehem on a donkey late at night and anxiously search for somewhere to stay. A stubborn innkeeper points out the ‘No Vacancies’ sign, and a desperate Joseph reluctantly leads his pregnant wife to a stable where she gives birth to Jesus that very same night.

The Christmas cards and nativity scenes portray the stable as warm and cosy, and complete with oxen and donkeys and an ankle-deep layer of remarkably clean straw, given that...