Beethoven
Bach
Mozart
Tchaikovsky
Vivaldi
Johan Strauss
Well, to be brutally honest, there aren't any famous composers, i.e. any composers that wrote anything well-known, from Australia. None of the composers that have their own category on WikiAnswers are Australian, and there are so many Australian composers I couldn't possibly give you a list of all of them.
10 famous oboe composers
.....
Beethoven
composers
.. ewan
Henry Purcell
paganini sarasatie vivaldi
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leopold mozart
Gloc9 Loonie
All these people were famous composers. Their names also happen to have six letters.