A short and [over-]simple history: In the first half of the 20th century French type was dominated by Deberny & Peignot (with Charles Peignot shifting the foundry from text type to display type). After WWII the Olive foundry became big, thanks in large part to Roger Excoffon's graphic bravado.* After that there was a dark ages of sorts, although there were some French individuals designing great type (like Ladislas Mandel and José Mendoza y Almeida - perhaps telling not native Frenchmen however). In the digital age the champion of French type design has been Jean François Porchez, although we have a number of great rising talents now, such as Christophe Badani.

* Two highly recommended recent books on Excoffon:
http://ypsilonediteur.com/fiche.php?id=95
http://www.adverbum.fr/roger-excoffon-rault-david-atelier-perrousseaux_o... (translated by yours truly :-)

hhp

Thank you very much for your valuable input
This book about Roger Excoffon looks great !

Cheers,
L.

BTW, I believe that Jean François Porchez and Christophe Badani can be considered as 21st century designers.
;-)