From the preface to the sixth edition of A History of Western Music by Donald Jay Grout and Claude V. Palisca:
"To be sure, the scope of what we teach and study under the heading of music history has broadened since Professor Grout wrote the first version of this book. The limits of Western music were generally agreed upon then, and hardly anyone doubted the value of studying its history. As populations everywhere become more diverse, the relevance of the Western art tradition to the music that is practiced and heard daily has understandably been questioned. Western Music in our title, which motivated an Internet retailer to award it the distinction of "best seller" in the category Country and Western Music, really acknowledges that the musical culture of Europe and the Americas is but one of several cultures whose distinguished histories deserve study."
Not quite the same definition of Western music there.
Of course, let's not forget the experience of Jake and Elwood.