Semi-automatic firearm - Wikipedia
The first successful design for a semi-automatic rifle is attributed to German-born gunsmith Ferdinand Ritter von Mannlicher, who unveiled the design in 1885.
The first semi-automatic rifle adopted and widely issued by a major military power (France) was the Fusil Automatique Modele 1917.
Don't forget the execrable Chauchat, introduced in 1907, which was a "machine gun" that was actually an "automatic rifle". Americans sometimes called it the "Sho-sho".
It jammed frequently (failure to extract) and was a dirt magnet -- the dirt then jamming the spent round in the chamber => failure to extract. It weighed 22 lb and was a beeotch to fire and aim properly. Please don't take my Chauchat away! (barf!)
It ranks right up there with the military flail as one of the poorest weapons ever issued to fighting men.