Rudbeckia hirta, commonly called black-eyed Susans, are a native wildflower here in the US.
Typically, when it comes to naming animals and plants, their common names stem from either the name of the person who discovered it, where it was found, or by their attributes. For example, pitcher plants hold water in them, much like a pitcher.
How did the name "black-eyed susan" come about? Was it discovered by a blonde lady named Susan who had a black eye at the time, and thought the flower resembled her appearance? Or maybe that it would resemble her if she had a black eye?