Short answers, pulled from the story.
Demon Slayer: Kimetsu no Yaiba was written and illustrated by Koyoharu Gotouge. It was serialized in Shueisha's Weekly Shonen Jump from the 15th of February 2016 to the 18th of May 2020, with chapters collected into 23 tankobun volumes.
By July 2025, Demon Slayer: Kimetsu no Yaiba had over 220 million copies in circulation including digital versions, with 164 million copies in Japan and 56 million overseas. It became the second manga series to sell over 100 million physical print copies in Oricon's records, after One Piece.
Demon Slayer: Kimetsu no Yaiba - The Movie: Mugen Train premiered in Japan on the 16th of October 2020 and became the highest-grossing anime and Japanese film of all time. A booklet given to theatergoers had a limited print run of 4.5 million copies.
According to Gotouge, the series' three biggest influences were JoJo's Bizarre Adventure, Naruto, and Bleach. Gintama influenced the comedy scenes, and the series' first editor Tatsuhiko Katayama noted that protagonist Tanjiro was partly shaped by Himura Kenshin from Rurouni Kenshin.
The series did not become a major hit until late 2019, more than three years after it began serialization in February 2016. Weekly Shonen Jump editor-in-chief Hiroyuki Nakano explained that success "hinged on word of mouth generated after the anime's run," as many viewers watched the 26-episode first season through streaming services after it ended.
The 23rd and final volume sold 2.855 million copies in its first week, the highest single-week sales figure for any manga volume in Oricon's history. It was also the first manga volume to sell over 4 million copies in Oricon's half-year sales ranking charts since Oricon began posting rankings in 2008.