Jean-Louis d’Usson was marquis d’Usson de Bonnac, and, according to his Wikipedia article, a noted French diplomat. He was born in 1663. I cannot trace backwards to his parents. He married Françoise Madeleine de Gontaut Biron who was born in 1692 (making her 15 years old - if this is her portrait). They married in 1715.
From youhuaaa.com/page/painting/show.php?id=37987; removed print in lower right.