This bayonet was the last of the French "sword-type" bayonets. It was manufactured to fit the French Model 1874 "Gras" Infantry Rifle, basically a refinement of the Model 1866 Chassepot Infantry Rifle. The "Gras" was manufactured from 1874 to about 1885.
"Usine de Steyr" (of Austria) made the French Model 1874 Gras Sword in 1877          
Several other countries used this bayonet, including Greece (these are marked "Waffenfabrik Steyr" or "Usine de Steyr"), Germany (many modified variants), Ireland, and others; Portugal also used a variant for their Portuguese Kropatschek Navy Rifle, but their bayonet has a straight back-edge on the grip (no hump).
http://arms2armor.com/Bayonets/fren1874.htm