Fete Champetre, May 1923 

 From Wikipedia:

A Fête champêtre was a popular form of entertainment in the 18th century, taking the form of a garden party. This form of entertainment was particularly popular at the French court where at Versailles areas of the park were landscaped with follies, pavilions and temples to accommodate such festivities.

While the term is derived from the French expression for a “pastoral festival” or “country feast” and in theory was a simple form of entertainment, in practice (especially in the 18th century), a fête champêtre was often a very elegant form of entertainment involving on occasions whole orchestras hidden in trees, with guests sometimes in fancy dress. Thus the simplicity of the event was often contrived.