The first name in Beyoncé’s stage persona “Sasha Fierce” is Sasha. Beyoncé used the name for the energetic performance alter ego associated with her 2008 album I Am... Sasha Fierce.
Beyoncé described Sasha Fierce as a persona that emerged when she performed. The concept helped distinguish the album’s performance-oriented material from the more intimate songs grouped under the “I Am...” title. The name therefore refers to a creative stage identity, not a separate musician.
The idea became especially associated with the songs and choreography on the album’s “Sasha Fierce” disc. “Single Ladies (Put a Ring on It)” is one of the best-known examples of that side of the project.
The persona is sometimes treated as though it were Beyoncé’s legal or birth name, but that is incorrect. Beyoncé’s full name is Beyoncé Giselle Knowles-Carter. Sasha Fierce was an artistic concept used during a particular period of her career.