After getting involved in the DIY scene in Boston as a teenager, Williams moved to Iowa. There, she wrote her first EP as Squirrel Flower and began setting up small tours for herself. This first EP, titled Early Winter Songs From Middle America, was self-released in 2015.
In 2016, Williams released her second EP titled Contact Sports on a St. Louis-based DIY tape label called It Takes Time.[4]
Williams' debut album, I Was Born Swimming, was released in 2020 via Polyvinyl Records.[5][6] The album was produced by Gabe Wax.[5] This anticipated label debut earned overwhelming praise from the likes of Gorilla vs. Bear,[7] NPR Music,[8] and Paste,[9] and she was named Rolling Stone Artist You Need To Know,[10]Stereogum's Artist to Watch,[11]The FADER's Gen F,[12] and The Guardian's One to Watch.[13] In May 2020, Squirrel Flower released the single "Take It Or Leave It", backed with her cover of Caroline Polachek's "So Hot You’re Hurting My Feelings."[14]
In March 2024, Williams was the first artist to withdraw from the South by Southwest festival due to sponsorships by "defense department contractors [that] make the weapons that the IDF uses to bomb Gaza." Eighty artists followed her lead, causing the festival to terminate their contracts with US Army and RTX Corporation for the 2025 festival.[15] Also in March 2024, she was featured on NPR Tiny Desk for the first time.[16]