The Gnome rotary engine took the aviation world by storm in 1909 with its light weight (60 kg) and power (34 hp). Le Rhône produced its first rotary engine in 1910. These two companies merged in 1915 and improved the rotary engine through World War I.
After the War Gnome-Rhône re-focused its efforts on radial engines, at first by license building Bristol products. Gnome-Rhône formed the basis of SNECMA after World War II.

History

1892: Louis and Laurent Seguin begin making petrol engines. They acquire a license to produce the Gnome gas engine from Oberursel.

1909: The Seguin brothers introduce their first production aircraft engine, the rotary Gnome Omega engine.

1910: Louis Verdet designs his own rotary aircraft engine.

1912: Louis Verdet establishes the Societe des Moteurs Le Rhône.

1915: Gnome buys out its rival Le Rhône to form the Societe des Moteurs Gnome et Rhône. Through World War I, the two companies retain their separate identities.

1921: Gnome-Rhône begins its successful program of building Bristol engines, then improving them.

1945: Gnome-Rhône vanishes into the nationalized group Societe Nationale d'Etudes et de Construction de Moteurs d'Aviation (SNECMA).