People celebrate birthdays to honor their birth and the beginning of a new year in their lives. The custom of celebrating birthdays began in ancient times but was not widespread until the turn of the 19th century. At that time, the perception of children was becoming more positive, and it became customary to celebrate with parties and customs like spankings for good luck or blowing out candles on a cake.
The Romans are considered to be the first people to have celebrated birthdays, but they only celebrated men's birthdays. There are no records of women's birthday celebrations until more than a millennium later. Friends and family members celebrated their birthdays privately, and the Roman government declared several holidays in honor of the birthdays of famous figures.
Because of its link to Roman's pagan culture, early Christians were opposed to birthday celebrations, and they did not even celebrate the birthday of Jesus until the fourth century. At that point, they put his birthday on the calendar near the date of the winter solstice.
The tradition of putting candles on cakes originated in Roman times, as the Romans made cakes with candles to honor their moon god. However, the tradition of having a cake at a birthday party did not become popular until Germans began doing it in the late 18th century.