Though she is portrayed (and indeed says so herself) as being "several" years older than the King and having had so much more life experience, in reality Mme Scarron, later The Marquise de Maintenon, was just under three years older than Louis. She was governess to Louis' 7 children by The Marquise de Montespan.
Scarron is portrayed as being "several" years older than Louis (in real life she was only 3 years older). Catherine Walker is in fact 14 years George Blagden's senior.