In Ovid's Metamorphoses, Niobe ruled the city of Thebes with her husband Anfione.  
Niobe considered herself the gods' equal, and in a moment of arrogance,
mocked the god Leto for having a mere two children to her own brood of
seven sons and seven daughters.  Leto avenged this act of hubris by
slaying all fourteen of Niobe's children.  Overwhelmed with grief, Anfione
took his own life upon learning of the deaths.  With her entire family gone,
Niobe turned to stone, from which her tears now endlessly flow. 

 

In keeping with BEMF's internationally-acclaimed tradition of presenting
little-known Baroque opera masterpieces, Steffani's Niobe is a stunning
achievement, blending poignant drama with powerfully beautiful music
to tell a story of human strength and weakness.  Niobe, Queen of Thebes
is by the Italian composer Agostino Steffani (1653–1728) with a
libretto by Luigi Orlandi.