Foreign Dub as Basis: The Italian Heidi dub is based on the German one, hence the presence of the German soundtrack by Gert Wilden (and not the original Japanese one by Takeo Watanabe).
Pet Fad Starter: The dog Joseph in this adaptation boosted the popularity of St. Bernard dogs, which is especially bizarre since he doesn't appear in the original novel.
Real-Life Relative: A rather curious case in the Latin American Spanish dub: Heidi and Klara (and also Peter)'s voice actresses, Cristina Camargo and Diana Santos, are cousins in real life, while Grandpa's voice actor, Francisco Colmenero, is their uncle.
Tourist Bump: The anime has drawn thousands of Japanese pilgrims to the Swiss Alps. No, really.
Misc.
The anime codified the concept of a butler as a Western-style personal assistant in Japanese popular culture. Hence why the go-to name for butlers in Japan is Sebastian.
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