Rameau

French composer Rameau is famous for some composing as royal french composer.
But he was also important for development of european music theory in fact.The system of accords with major and minor is by him.In his time accard system thinking was new.People like bach are composing beauty in four or five independant melody lines one over the other with all interdependance mega complexity.But almost all western pop and rock music and Jazz is based on more or less complex accord thinking of Rameau with an additive leading melody line.

Most important tunes :

Pieces de Clavecin Allemand,
Boiteuse
Hippolyte especially Act 3 Scene 9

O.F.D This list is still incomplete