Arthuria Pendragon, the gender bend spin off of "King Arthur" in tales of valor for the holy grail war.
She is from an anime called "Fate: Zero", and has a lot of other forms. (Saber Alter and Saber Lily being some of them)
This is by far one of the easiest cosplay's I've don so far. All I needed to do was re-style my wig and fix the polo and jacket.