Incidentally, the reason the title includes "Shinsen" (newly compiled) is that it meant to indicate the re-compilation of "Shizoku-shi" (a book containing information on the clans), which ended up just as a plan; consequently, it doesn't infer the existence of any previous edition of the clan-name register.
なお、書名に『新撰』とつくのは、企画倒れで終わった『氏族志』のやりなおしという意味であって、『新撰姓氏録』以前に『姓氏録』が存在していたわけではない。