Heidi was a joyful and free-spirited young girl who is orphaned as a toddler. At the beginning of the story, she is five years old. Heidi loves her grandfather (uncle Alp) and the beauty and fresh air of the mountains. Only Fräulein Rottenmeier calls her by her given name "Adelheid", in some translations "Adelaide".

In the town of Domleschg lived two brothers. The older wasted the family fortune on drinking and gambling, while the younger ran away to serve in the Kingdom of the Two Sicilies's Army in Naples. Years later the younger brother returns with a son, Tobias. After Tobias serves an apprenticeship to Mels, father and son move to Dörfli ('small village' in Swiss German) in the municipality of Maienfeld. The villagers spread rumors about the father's life in Naples. The man becomes known as The Alm-Uncle, as he lives in seclusion on the mountain Alm. Two village girls, sisters Dete and Adelheid, befriend Tobias. Adelheid and Tobias marry and have a daughter, also named Adelheid but affectionately nicknamed Heidi. Soon after, Tobias is killed in a work accident and Adelheid dies of shock. The Alm-Uncle holds this against God and becomes bitter.

Heidi is raised by her maternal grandmother and Dete in Maienfeld. Shortly after the grandmother's death, Dete is offered a job as a maid in the big city, and takes 5-year-old Heidi to live with the Alm-Uncle. He resents Heidi's arrival, but the girl's intelligence and cheerful yet unaffected demeanor soon earn his love. Heidi befriends her new neighbors: young Peter the goatherd, his mother Brigitte, and his blind maternal grandmother. With each season that passes, the mountaintop inhabitants, especially Peter and the grandmother, grow more attached to Heidi, and she to them. However, the grandfather refuses to allow Heidi to attend school, quarreling with the local pastor and schoolmaster when they try to encourage him to do so, and Heidi is illiterate as a result.

Three years later, Dete returns to take Heidi to Frankfurt to be a hired lady's companion to a wealthy girl named Klara Sesemann, who is unable to walk and regarded as an invalid. Klara is charmed by Heidi's simple friendliness and her descriptions of life on the Alm, and delights in all the funny mishaps brought about by Heidi's naïvety and lack of experience with city life, but the Sesemanns' strict housekeeper, Fräulein Rottenmeier, views the household disruptions as wanton misbehavior, and places the free-spirited Heidi under more and more restraint, forbidding her to talk of the Alps or to cry for home. Soon, Heidi becomes terribly homesick for the Alm, and grows alarmingly pale and thin. Her one diversion is learning to read and write using a collection of Biblical stories, motivated by Klara's grandmother Frau Sesemann who shows her trust and affection, and encourages her to believe in God and to pray. Later Frau Sesemann gifts Heidi the book.

Heidi's homesickness leads to episodes of sleepwalking where she goes downstairs and opens the front door, which the household initially takes as the work of ghosts. The family doctor recommends she be sent home before she becomes seriously ill. She gladly returns to the mountains laden with presents for her friends and the book from Frau Sesemann, but finds one of her greatest pleasures is reading hymns to Peter's blind grandmother, who can no longer do so for herself. Her faith in God speaks to something in the Alm-Uncle. One day Heidi reads to him "The Prodigal Son" from a book Frau Sesemann gave her. That night Alm-Uncle prays for the first time in years. He accompanies Heidi to church, and that winter takes accommodation in the village so that she can attend school.

Heidi and Klara continue to keep in touch and exchange letters. A visit by the doctor to Heidi leads him to recommend that Klara visit Heidi, believing that the mountain environment and the wholesome companionship will do her good. Klara makes the journey the next season and spends a wonderful summer with Heidi, becoming stronger on goat's milk and fresh mountain air. Peter, jealous of Heidi's and Klara's friendship, pushes her empty wheelchair down the mountain. He is soon wracked with guilt about what he did and ultimately confesses to it. Without her wheelchair, Klara has no choice but to learn to walk; she attempts to do so and is gradually successful. Her grandmother and father are overcome with joy to see Klara walking again. The Sesemann family promises to provide permanent care for Heidi, if there ever comes a time when her grandfather is no longer able to do so.

All published appearances of Heidi from before January 1, )-(95)}} are public domain in the US

Some notable appearances are list below:

*Heidi: Her Years of Wandering and Learning (1880)
*Heidi: How She Used What She Learned (1881)

* Dell Junior Treasury #6 - Heidi

*Have You Got Any Castles? (1938)

*[https://en.wikipedia.org/wiki/Heidi Wikipedia]
*[https://tvtropes.org/pmwiki/pmwiki.php/Literature/Heidi TV Tropes]
*[https://comicvine.gamespot.com/heidi/4005-91225/issues-cover/ ComicVine]
*[https://comicbookplus.com/?dlid=31687 Comic Book Plus]
Category:Literary Characters
Category:1880 Debuts
Category:Johanna Spyri - Creator
Category:Female Characters
Category:Juvenile Heroes
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Category:Swiss Characters
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