Conversation so far:
when was katy parry's first album under Katy Perry's stage name?
March 6, 2001.
what did she do between 1999 and 2001?
2001, and went on tour that year as part of Phil Joel's Strangely Normal Tour while also embarking on other performances of her own in the United States.
Was her first album as Katy Perry a hit?
Katy Hudson received positive reviews from critics, though was commercially unsuccessful.
When did Perry start gaining commercial success?
2005.

Question: What was it that started gaining her popularity?
Self-contained rewrite: What started gaining Perry popularity in 2005?