Born in London, England and raised in California, Amelie Simpson started playing guitar at age nine, after receiving the instrument as a Christmas gift. She learned songs by watching YouTube videos from online guitar teachers Justin Sandercoe and Marty Schwartz. Two years later, at the age of 11 she began to post her own cover versions of songs on her YouTube channel and she started performing at local open mic nights in San Diego.
Simpson made her performing debut at the San Diego County Fair in 2017, at the age of 13, playing a 90-minute set on the Showcase stage. In 2019, she wrote and recorded her first original song, "What My Name Is", released on Spotify and iTunes.