music is more than just notes, though. there are so many subtle factors that determine a "style". Blues was invented by black slaves kidnapped from Africa, and brought to a new continent where they interpreted European and other styles of music in new ways with a mixture of instruments in the African and European traditions. So while European music did have the notes of the blues scale, it could never have any of he nuances or idiosyncrasies that gave it the "blues sound" or "blues feel", those things came from African music. Especially things like syncopation and poly rhythm

Also, blues does not necessarily conform to the notes of a blues scale, or western tonality, because there are many notes between the notes.. which some feel is the signature attribute to this music..... on the piano a similar feeling is achieved with note clusters (according to Duke Ellington)

this is a very interesting topic for me... if you are interested in learning about the history of blues and jazz in the context of world history, I highly recommend a book by Ned Sublette called "The World That Made New Orleans"