To those who remember a little French history, this is a clear reference to King Louis XIV, dubbed le Roi Soleil because of his grandiose lifestyle and long reign -- 72 years, to be exact -- the longest of any monarch in history. It was he who built the opulent palace at Versailles, in the southwestern suburbs of Paris. His power in Europe was undisputed for many years.
Once Federer wins his 15th Grand Slam tournament (later this month at Wimbledon?), the French will have to think of another analogy, as there's nothing particularly noteworthy about Louis XV. But for now, the classy Swiss, being called an "absolute monarch", is wearing the title well -- and deservedly.