It happened around 2000 years ago. When Mary was about to give birth after she and Joseph arrived in Bethlehem, they were desperately look for a room to stay. Even though every facility in town was full, one merciful man allowed them to stay in his barn which was where Jesus was born shortly thereafter. Years later when the man realized that Jesus was born on his property and was very famous, he hoped eventually somewhere a lodging franchise would in some way honor his inn that helped create a holiday.
