Although moderately successful in the US upon release, the song went viral on TikTok and charted internationally after American singer-songwriter Olivia Rodrigo covered it on BBC Radio 1 in the United Kingdom, causing it to reach number one in various countries including Australia, Belgium (Flanders), Ireland, the Netherlands, and the United Kingdom, as well as charting in the top 10 in Canada, New Zealand, and the United States.

An early version of the song was performed on a live stream on Kahan's Instagram, broadcast some time shortly prior to November 3, 2020.

It became successful quickly, prompting him to finish writing the song, which "ended up taking a long time".

[1] The song title refers to a term for autumn in New England, the period after Halloween before the winter snow begins,[3] which Kahan called "a time of transition" and "super depressing" as "it just means that winter is coming soon and it creates a lot of anxiety" and "nobody really likes it".

[4] This song is a folk piece written in A major, with a tempo of 115-118 BPM and a 4/4 time signature.