I believe the two most significant figures in the development of classical music [and beyond] were Johann Sebastian Bach, the German born composer of the Baroque Era; and Franz Joseph Haydn, the Austrian composer in the Classical Era of classical music.
What is an amazing coincidence [or more accurately stated-by the grace of God], both of these significant composers were born on the same day, March 31, forty-seven years apart.
From my post: ‘Happy Birthday Johann Sebastian Bach‘: The quintessential Baroque composer, Johann Sebastian Bach, was born 336 years ago in Germany on either March 21, 1685 or March 31, 1685 – this time dispute relates to the change of calendars [Julian to Gregorian] during that time period. Most today celebrate Bach’s birthday on March 31.”
“When you say Baroque music, the name Bach must first come up. He is one of, if not the most, influential person in classical music with his musical inventions, techniques and great compositions. Without Johann Sebastian Bach, it is doubtful, in my opinion, that classical music would have developed as fully as it did. Most of the great composers in the Classical and Romantic Era’s to follow [and even with children learning how to play classical music today] got/get their foundation from Bach’s musical inventions.”
“Bach was the main developer of the polyphony technique that was a main characteristic in the Baroque period of music. Polyphony means ‘many voices’ and in the compositions was demonstrated by different thematic lines [voices] of music being played at the same time.”
So, I do not believe it is a stretch to say, the very foundation of not just classical music but all music began with Johann Sebastian Bach.
If the foundation began with Bach, who continued with the development of classical music. I believe that torch was passed from Bach to Franz Joseph Haydn, also known belovedly as “Papa” Haydn from the admiration of the people who loved his playful and sunny  symphonies that put a smile on many faces. The people loved their Papa Haydn.
From my post, ‘Happy Birthday Franz Joseph Haydn’: “Franz Joseph Haydn: “(born March 31, 1732, Rohrau, Austria—died May 31, 1809, Vienna), [was an] Austrian composer who was one of the most important figures in the development of the Classical style in music during the 18th century.”
“Franz Joseph “Papa” Haydn was one of the most important pioneers in the development of classical music. He was the creator of the classical symphony. He gave the future great masters much to study from as he wrote an amazing 104 classical symphonies. That is not all. This great composer did in the development of classical music. He also developed the sonata style of composition [exposition, development, recapitulation] that became a staple of composers of classical music.”
“Papa Haydn also was a leader in developing the string quartet. He was prolific in his string quartets and it led the way to the great string quartets from the masters that followed Haydn’s lead.”
So, without the foundation of Bach to the development of Haydn, would classical music [and beyond] have developed as it did? We can never know of course, but what we do know is these two iconic giants of classical music may be the two most important figures in the greatness of what classical music became.
To read the whole posts of these two geniuses, and also to enjoy some of their great music from each, please click on: