Anne became Louis XIV's mistress in 1669 when he was staying at the Château of Chambord where Anne was also present. At the time, Louis' affections were split between Louise de La Vallière and her future successor Madame de Montespan. Some time later Anne gave birth to her second son, Hercule Mériadec de Rohan (future Prince of Soubise yet styled at birth as the Duke of Rohan-Rohan).
In January 1674 Anne became a Lady-in-waiting to Queen Marie Thérèse and five months later she gave birth to another son Armand Gaston Maximilien de Rohan. It was by then common knowledge that the King and Anne were lovers and it was commonly said that her son was really from Louis XIV and not Monsieur de Soubise although he acknowledged the baby as his son. Although nothing was proved, Louis XIV did allot a large sum of money to the compliant husband, "in consideration of his services." In the portraits of the time, the similarity between the king and Armand is obvious. Her husband quickly became wealthy.
The couple's affair ended in 1675 having been on an off for some six years.