“It’s a Wonderful Life” did not become widely popular until the mid‑1970s, about 30 years after its original release, when it began airing constantly on American television each Christmas season.

Initial release and flop

  • The film was released in late 1946 and went into general release in early 1947, earning modest box office returns and ranking only 26th among that year’s releases.
  • Despite several Academy Award nominations, it failed to recoup its production costs at the time and was considered a commercial disappointment.

Copyright lapse and TV era

  • In 1974, the film’s copyright was not properly renewed under the then‑current U.S. law, which caused it to effectively enter the public domain.
  • Because TV stations could broadcast it without paying royalties, they began running it repeatedly during the Christmas period throughout the mid‑ to late‑1970s.

Rise to classic status

  • By around 1976, it had become a regular Christmas staple on American television, and its status shifted from forgotten flop to beloved holiday classic.
  • Frequent annual broadcasts helped new generations discover it, and over time it came to be regarded as an inspirational, essential Christmas film.

TL;DR: It was released in 1946 but only really became popular in the mid‑ to late‑1970s, after a copyright lapse let TV stations air it constantly at Christmastime.

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