The concept of the rotary engine (the whole engine running around a fix crankshaft) is a french innovation.

Although rotaries where made in UK, Italia and Germany, the french ones where seen as the best ones; to the extent that french engines (removed from crashed planes) where fitted to German aircrafts.

The last Fokker Dr. I of Manfred von Richtofen had a french engine! And Clerget engines where (and still are) the most sought after french engine of WWI