Branwen

Also could mean “blessed raven”, which is definitely my favourite meaning.

'Alternatively could mean "a girl with black hair and white skin." In Mabinogi, Branwen is Bran's sister; they are male and female aspects of the Celtic war deity.'
Source: http://www.amethyst-night.com/names/welshfem.html

According to Welsh mythology, Branwen (daughter of Llyr) is one of the three greatest queens in the land and the most beautiful girl in the entire world.