The organization of the list of bandleaders by "Nationality" in this article seems a bit arbitrary and perhaps not very useful?  Would a different organization be better?  For example, "by era" ("pre-1900", 1900~1909, 1910s, 1920s, 1930s, etc.?) or perhaps simply an alphabetical listing ignoring nationality or era?   It's also not clear if the nationality headings listed should refer to the nationality of the band or to the nationality of the bandleader.  For example, Toshiko Akiyoshi led a North American big band for 30 years (10 years in Los Angeles and 20 years in New York) but she, herself is a Japanese citizen - although she has resided in the US for over 50 years.