The Fleur de Lis dates back to ancient Egypt, and has always represented power, enlightenment and good luck. It has also had some degree of mystery.
As the story goes, it was either Louis X or Louis XI who was about to lose France in a battle. He was out manned, our armed, the other army was better fed and stronger. The situation seemed hopeless. He put the already ancient symbol on his shield for power and luck, and to everyone's surprise, he won! Winning the battle and saving France, he declared the Fleur de Lis to be the symbol of France.
There were times when it was illegal for anyone other than French nobility to use or display the Fleur de Lis. This might explain why the symbol is so closely associated with the impressing of class and elegance.
Another part of this which seems debating is whether Fleur de Lis means Flower of Louis (which was always my understanding) or just a lily flower.
Fleur de Lis pendant, shown here in 18K with diamonds, and my signature overflowing dots of diamonds, representing overflowing abundance.
There are so many available versions of the Fleur de Lis Collection. Here are a few examples: