Beyoncé used the performance alter ego Sasha Fierce during the late 2000s.
The name became especially prominent with her 2008 album I Am... Sasha Fierce. Beyoncé described the project as a double album: the “I Am...” disc emphasized more personal ballads, while “Sasha Fierce” represented a bolder, more assertive stage persona.
Songs associated with that era include “Single Ladies (Put a Ring on It),” “If I Were a Boy,” “Halo,” and “Ego.” The concept reflected a distinction between Beyoncé’s private self and the confident character she inhabited during performances. It was a branding and artistic device rather than a separate legal identity.
Beyoncé later said she had retired the Sasha Fierce persona because she no longer needed to separate her stage confidence from her personal identity. The name is therefore most closely linked with the 2008 album cycle and its surrounding performances, videos, and promotional material.