Louis Napoleon Bonaparte was the nephew of Napoleon Bonaparte.
Because plantation owners were mainly in the southern states. Also because there were many people that bought them from the south than anywhere else :)
I believe she tells them to cover their ears with wax. The Sirens were known to enhcant sailors with their music and songs and lure them to their deaths. To prevent that Circe had them plug their ears so they wouldn't be enchanted, and go to their death.
