I will nominate Columba
by Prosper Mérimée. I nominate this based on the fact that Mérimée himself is not that well known and to the extent that he is it is for his story Carmen
upon which the famous opera by Bizet was based.
Set on the island of Corsica in the 19th Century it is the tale of a young solider who after serving in the French army returns home when his father is murdered. There his sister incites him to seek a revenge killing on the rival family that she is convinced murdered their father. Very colorful portrait of the Corsican culture of the time.
Wikipedia biography of Prosper Mérimée
This is available here at MR
and at PG