Original: The prelude to Charpentier's setting (H.146 in Hugh Wiley Hitchcock's catalogue) is well known in Europe on account of its being used as the theme music for some broadcasts of the European Broadcasting Union, most notably the Eurovision Song Contest.
Simplified: The prelude to Charpentier's setting (H.146 in Hugh Wiley Hitchcock's catalogue) is well-known in Europe because it is used as the theme music for the European Broadcasting Union, most notably the Eurovision Song Contest.