Mark K.  Ehlert wrote answering to Walter Meyer's questions about the
origins of the Orchestre Revolutionnaire et Romantique:

>I don't have a definite answer here, but my speculation is that Gardiner
>came up with the rather cumbersome title: he seems to be a big fan of
>French music, and the title pretty much describes the historical period
>from which their music originates.  If I remember correctly, there was
>mention on the monologue CD which accompanies the Beethoven symphony that
the English Baroque Soloists who recorded the "Missa Solemnis" were
>actually the ORR, but the latter title hadn't been used for whatever
>reason.

John Eliot Gardiner's words about his ORR are what follows (I'm quoting
accordingly to what I've listened to):

   "To some extent, our Orchestre Revolutionnaire et Romantique is
   modelled on that of the Societe des Concerts du Conservatoire, that's
   to say the orchestra composed of Laureates and Professors of the
   Paris Conservatoire, founded by Habeneck in 1828.

   This orchestra achieved several things.  They virtually appropriated
   Beethoven for themselves and their performances of these symphonies
   were prepared meticulously, quite unlike those Beethoven witnessed
   during his lifetime.  For the first time, uniform bowings were adopted,
   and the scores seemed to have been performed with unaccustomed accuracy
   and precision.

   The orchestra took destiny by the scruff of its neck in typically
   French fashion, and showed the musical world where the future lay.
   The impact on Berlioz, Liszt, Wagner and countless other musicians
   who heard these performances, was enormous.  It was precisely in
   order to bring out the "revolutionnaire" as well as the "romantique"
   in Beethoven, that our orchestra, the Orchestre Revolutionnaire et
   Romantique, came into existence in 1989, albeit not yet bearing that
   name in public, with our recording of his "Missa Solemnis", opus
   123".

I hope it helps.

Regards,
Wilson Pereira.