What stage alter ego did Beyoncé use during performances in the late 2000s?

Beyoncé used the stage alter ego Sasha Fierce during performances in the late 2000s.

The name became especially prominent with her 2008 double album I Am... Sasha Fierce. The project contrasted two sides of her artistry: the “I Am...” disc emphasized personal and emotional songs, while the “Sasha Fierce” disc focused more on energetic, confident performance tracks.

Beyoncé described Sasha Fierce as a persona that emerged when she was performing, allowing her to separate her private self from her highly theatrical stage presence. Songs associated with that era include “Single Ladies (Put a Ring on It),” “If I Were a Boy,” “Halo,” and “Diva.”

The persona was not a separate performer or legal identity. Beyoncé later said she had retired Sasha Fierce because she no longer needed the separation. “Queen Bey” is a later nickname, not the alter ego named in the album title.