The Heidi books are among the best known works of Swiss literature.
Adelheid alias Heidi is an orphaned girl initially raised by her aunt Dete in Mayenfeld, Switzerland. In order to get a job in Frankfurt, Dete brings 5-year-old Heidi to her grandfather, who has been at odds with the villagers for years and lives in seclusion on the alm. This has earned him the nickname Alm-Öhi ("Alp-grandfather" in the Graubünden dialect). He at first resents Heidi's arrival, but the girl manages to penetrate his harsh exterior and subsequently has a delightful stay with him and her best friend, young Peter the goat-herd.
Dete returns 3 years later to bring Heidi to Frankfurt as a companion of a 12-year-old invalid girl named Clara Sesemann. Heidi spends a year with Clara, clashing repeatedly with the Sesemanns' strict housekeeper Miss Rottenmeier and becoming more and more homesick. Her one diversion is learning to read and write, motivated by her desire to go home and read to Peter's blind grandmother. Heidi's increasingly failing health and several instances of sleepwalking (it is implied that she has inherited a propensity to epilepsy from her mother) prompt Clara's doctor to send her home to her grandfather. Her return prompts the grandfather to descend to the village for the first time in years, marking an end to his seclusion.
Heidi and Clara continue to write to each other. A visit by the doctor to Heidi and her grandfather convinces him to recommend that Clara journey to visit Heidi. Meanwhile, Heidi teaches Peter to read and write. Clara makes the journey the next season and spends a wonderful summer with Heidi. Clara becomes stronger on goat's milk and fresh mountain air, but Peter is jealous of Clara and pushes her wheelchair down the mountain to its destruction. Without her wheelchair, Clara attempts to walk and is gradually successful. Clara's Grandmother and Father are amazed and overcome with joy to see Clara walking. Clara's wealthy family promises to provide a shelter for Heidi, in case her grandfather will no longer be able to do so.
Other versions of the story include:
The novel was also the inspiration for a 1990 motion picture Courage Mountain, which was a sequel of sorts to the original book and features a teenage Heidi.
Heidiland, named after the Heidi books, is one of the main tourist areas in Switzerland, in particular for the Japanese. Maienfeld is situated near the Liechtenstein border in Kanton Graubünden, it is home to around 40,000 people, and still has the spectacular alpine views of Heidi's day.
There are some major differences between the original Heidi by Johanna Spyri and Heidi Grows Up and Heidi's Children by Charles Tritten. These include;
"Heidi" has been adapted as a musical drama by Shaun McKenna (lyrics), Stephen Keeling (music), Stefan Mens and John Havu. Anja Hauptmann created the German translation. The show was first produced as a large open-air production in Walenstadt, Switzerland in 2005. The musical returned to Walenstadt in 2006 and a new theater production was performed in Dessau, Germany in 2006-2007.
The plot is an intertwining of Johanna Spyri's first Heidi novel with the life of the author. In a commitment to her dying son Bernhard, Johanna promises to set down her childhood remembrances in a novel. Parallels of action occur between the real world of Johanna and the fictitious world of Heidi with moments where the two worlds collide. The work does not rely on the normal clichés associated with Heidi adaptations but provides insights into the life and times of the author.
A sequel to the above mentioned musical written by the same team, with a German translation by Stefan Huber, premiered on the open-air stage in Walenstadt, Switzerland in the summer of 2007. The work follows a similar idea of intertwining the life of Johanna Spyri but this time with the second Heidi novel. A twist in the plot is the figure of Johanna meeting and falling in love with a long time friend Conrad Ferdinand Meyer in Montreux as she is writing the second Heidi novel, which nearly ends in the book having a quite different outcome. The musical ends with the death of Johanna Spyri and the reappearance of Heidi who leads Johanna "home".
The musicals are published by Gallissas Theaterverlag und Mediaagentur, Berlin.
"Heidi" became an internationally popular first name as a direct result of the novel. It is an affectionate diminutive of the name Adelheid (English: Adelaide), which means "nobility" or, more loosely, "of noble birth". In the book, the stiff and formal Miss Rottenmeier makes a point of calling Heidi only by her formal name "Adelheid", deeming a nickname inappropriate.
The number of girls named Heidi in the U.S. rose sharply for several years immediately after the broadcast of the 1968 television film starring Jennifer Edwards (see above).
In German-speaking countries, Heidi is also used as a diminutive for other names, such as Heidrun, Heidelinde, and Heidemarie.