I highly doubt Rihanna is the first girl to rock red hair. Lots of artist have. I don't see what all the hype about Katy Perry and Rihanna is. They are okay I guess if you like that kind of music and not looking for real talent or singing.

In terms of Rihanna being a trend setter with red hair, that is dead wrong. Lots of artist have rocked that ugly color. For example, Kelly Rowland did in 2003, Toni Braxton 2005 - 2006, Gloria Estefan, Cher, Chery Cole, Monica, Trina, and even Fantasia back in 2008. Unless you are a natural red head (usually someone that also has freckles) that is a color an artist will try out for a while to promote something and move on to something more attractive.