Inevitably there's going to be some kind of subjectivity to any answer. I'll take your word "innovative" to mean "unprecedented". These are my suggestions:
Doubtless others would chip in with such luminaries as Claudio Monteverdi (1567-1643), the first composer to break with the Renaissance polyphonic musical traditions and to launch what is now known as the Baroque period; Beethoven (1770-1827), who realised the potential for the personally expressive and the titanic in music; and my own beloved Wagner (1813-1883), who revolutionised both Opera and the orchestra and - in the view of many - pushed music to the boundaries of tonality, making Schoenberg (1874-1954) inevitable. Speaking of which - Schoenberg, Stravinsky (1882-1971) and Debussy (1862-1918) each played their part in breaking some boundaries. Schoenberg finally ditched the major-minor tonal system that had been the norm since about 1650; Stravinsky turned the previous Romantic century around completely; and Debussy was one of the first to bend the tonal system beyond breaking point, leaving only its remnants in his work. However, all of the above could be seen as relying on their predecessors rather than being truly independent of them.
For my money, however, the most innovatory composer of all time is Franz Liszt (1811-1886). No, not the Liszt of the Liebestraum, but the Liszt of the late piano music. He pioneered techniques that were decades ahead of his time. He was the first to write a piece of whole tone music (one based on a scale consisting purely of tones, not a mixture of tones and semitones as are the major and minor scales of tonality). Much of this late stuff is atonal - in fact, one of the pieces is his Bagatelle without Tonality. His dissonances are simply inexplicable in terms of any conventional tonal treatment; they include a tone cluster, a la Ives and Cowell. Liszt himself wrote on the cover of one of these experimental pieces, the Czardas Macabre (which consists of a string of parallel 5ths, a progression forbidden for about half a millennium), "Is it allowed to write such stuff, or listen to it?" As an index of how revolutionary this late music was, iconoclasts and progressives one and two generations later - namely, Debussy and Bartok respectively - were gobsmacked when they discovered this stuff. Very dark music, most of it, and thus very much an acquired taste. Enjoy!
Robert Schumann was the composer of the most famous classical songs. He wrote many song cycles which are groups of songs on the same topic. Schumann wrote hundreds of songs in his lifetime.
If you mean from the Classical Era, then definitely W.A. Mozart.
Igor Stravinsky!
no, Haydn is a composer of the classical era
Yes.
Robert Schumann was the composer of the most famous classical songs. He wrote many song cycles which are groups of songs on the same topic. Schumann wrote hundreds of songs in his lifetime.
Yes he was, at least mostly. He composed at least most of his pieces in the Classical style.
No, Mozart was a classical composer.
If you mean from the Classical Era, then definitely W.A. Mozart.
Wolfgang Amadeus Mozart was a Classical composer who was born in Austria.
Igor Stravinsky!
Frédéric Chopin is often regarded as the most successful freelance composer of the classical era. He achieved significant acclaim while living in Paris, where he composed, performed, and taught without being tied to a court or institution. His unique style and innovative compositions garnered a dedicated following, allowing him to thrive independently. Chopin's success as a freelance musician helped redefine the role of composers in the 19th century.
A classical music composer (in the romantic style).
no, Haydn is a composer of the classical era
Mozart is a classical composer. He was an Austrian. He spent most of his lifetime in Salzburg and Vienna.
wolfgang amdeus mozart
Yes.