This piece is called Louis XV donnant la Paix à l'Europe - Louis XV Bringing Peace to Europe. The work was done by François Lemoyne, a rival painter to de Troy. The piece can be viewed at the salon de la Paix.
The Salon of Peace was built at the same time as la Salon de la Guerre, Salon of War. The painting was placed there in 1729, and hangs above the mantelpiece surrounded by 6 busts of the Caesars.
When the painting was added the salon was attached to the Queen's Apartments, and used for musical performances by the chapel musicians. Marie Antoinette used the room for playing cards with men and women of the court.
In the painting, our main figure is Louis XV. Peace appears in the form of the olive branch between him and Europe. An ideal King, taking care of France right away! In the portrait he is only 19.
In return he is being offered twin baby girls. The babies are offered by Fertility, the swanky nude. His first children were twin girls and he loved them more than anything, really. What is ironic here, is that we have a portrait of Louis as King but as father. No Queen in sight! And yet it hangs in her apartments. A pleasant reminder of her family or...