[4] As soon as the Marie Louise d'Orléans arrived in Spain, she became fast friends with Madame de Villars and her husband, the French ambassador, who translated for the couple during their wedding ceremonies as neither the King nor his new wife spoke the language of the other.
"In the pre-industrial world, married couples worked cooperatively with the purpose of achieving a specific objective," in this case information gathering and diplomacy.
The new Queen consort was not yet 18 and had great difficulty making that adjustment and she took advantage of the diplomatic access granted to Madame de Villars so they could spend hours together speaking and singing in French.
[2] These arrangements also gave Madame de Villars the opportunity to convey messages privately between the French King and the Spanish Queen.
"During the entire decade of 1680, the French embassy sought to make of Queen Marie-Louise a political tool in the service of her uncle [Louis XIV]."