Chlöe Swarbrick was born in Auckland after her mother, a New Zealander, moved home from London without her biological father.
The man she calls Dad adopted her when she was 3, but Swarbrick said she was 12 before she learned that he wasn't her biological father.
Swarbrick said she has a difficult relationship with her mother.
"If I have to blame Mum for screwing me up to some extent, I also have to blame her for my drive," she told VICE.
Swarbrick also opened up on her family background, saying she moved from Auckland to London to Port Moresby as a child.
Her experience in Papua New Guinea was "weird" and "sheltered", she said.
She said she lived in a compound guarded by men with AK-47s, living near "real, very serious poverty".
Swarbrick also talked about dealing with her newfound profile after her mayoral campaign.
"It was really weird having this minor celebrity, and I still struggle with that," she told VICE.
"I'm all for constructive critique, but [you get a lot of criticism] from people on the internet. Particularly as a young woman, I think."
Running as an independent, the 22-year-old placed third in the Auckland mayoral race last year with 29,098 votes despite having no political background and minimal financial support.
Swarbrick is standing for Parliament in Maungakiekie, and is listed at 13 in the Greens draft party list.