Compagnia Nazionale Aeronautica was a manufacturer of aircraft and aircraft engines established in Italy in 1920 by Count Giovanni Bonmartini. Together with a group of World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 veteran pilots, he operated a flying school in Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

 from a field that would eventually be developed into Littorio airport. For the next decade or so, CNA also developed their own aircraft and engines to power them. Bonmartini had also worked on an advanced racing motorcycle engine, the GBR in another partnership, and eventually CNA acquired the rights to this as well.

In 1934 Bonmartini sold CNA to Caproni

Caproni

thumb|right|300px|[[Caproni Ca.316]] seaplane at its moorings.Caproni was an Italian aircraft manufacturer founded in 1908 by Giovanni Battista "Gianni" Caproni....

. In turn, Caproni sold rights to the GBR engine to Gilera

Gilera

Gilera is an Italian motorcycle manufacturer founded in Arcore in 1909 by Giuseppe Gilera. In 1969 the company was purchased by Piaggio, which now holds six marques and is the world's fourth largest motorcycle manufacturer.-History:...

, who developed it as the Rondine.