Candles are not only used for lighting, but also for religious and celebratory purposes. In the case of a death, the Romans had the practice of putting candles on the grave.
And so, according to Roman and Germanic traditions, a candle was the symbol of life.
In the Catholic Church, lighting many candles comes from a very ancient custom. One of the first examples of public lighting dates back to the fourth century, when the Christian emperor Constantin gave the order to light the entire city of Constantinople on Christmas Eve, with lamps and wax candles.
Other sovereigns also largely used candles. The king Alfred the Great (who reigned from 871 to 901), gave the order to make candles for measuring time. These beeswax candles were divided by lines. Six candles, lit one after the other, burnt together for 24 hours. Chronometer candles were still used until the Second World War.
Candles are still used as a symbol accross the world in numerous religious and secular practices, from religious festivals all around the world to birthday celebrations.