When did the tradition of birthday parties first start?

Answer 1

It is thought that the large-scale celebration of birthdays in Europe began with the cult of Mithras, (Mithras was the nominal object of devotion in a Greco-Roman mystery religion of late antiquity.) which originated in Persia but was spread by soldiers throughout the Roman Empire. Before this, such celebrations were not common; and, hence, practices from other contexts such as the Saturnalia were adapted for birthdays. Because many Roman soldiers took to Mithraism, it had a wide distribution and influence throughout the empire until it was supplanted by Christianity. The Jewish perspective on birthday celebrations is disputed by various rabbis.

Answer 2

The birthday party tradition began thousands of years ago. People believed that a person could be visited by good or evil spirits on the day they were born. So family and friends gathered together to protect the person from evil spirits on that day, thus, the birthday party was born.

Answer 3

they felt like it