Some of its entries are more familiar or popular than their book counterparts. Lucy of the Southern Rainbow, Alps Story: My Annette, Katri, Girl of the Meadows, Bushbaby and even Romeo's Blue Skies are some of the examples of this.
In some European countries (such as France), Tom Sawyer is more well known in its 1980 anime form than in its literary form or any other adaptation (mostly because it's a seminal novel of American literature that's not School Study Media in Europe).
All Animation Is Disney: The franchise never adapted Adventures of Huckleberry Finn, but that doesn't prevent many people from thinking Huckleberry no Bōken (1976) and Huckleberry Finn Monogatari (1994) were part of it. Doesn't help that those were made in the same timeframe as World Masterpiece Theater series and had some similar animation (the main character looks markedly different compared to his WMT counterpart in Tom Sawyer, that said).
Archive Panic: And how! The series has 26 entries (31 if you include Heidi, Moomin, Dororo, Rocky Chuck and Andersen Stories) and each of their episodes are around 25 minutes. Then, there are A Dog of Flanders and 3000 Leagues in Search of Mother movies.
Broken Base: Some viewers think that the entries involved with Hayao Miyazaki and Isao Takahata are the best in the series, others think that the shows from late 70's to 1980's are the best, and there are some people who love the series because of Nostalgia Filter.
In Japanese fandom, there are some arguments whether Tico of the Seven Seas is part of WMT or not. Mostly, it has something to do for being the only show that isn't adapted from any novels.
Although not every series was subjected to this, some shows had to tone down its stories to be more appropriate for children, causing some fans to have polarizing reactions to them.note For example, in Les Misérables: Shōjo Cosette, Fantine isn't made to go into prostitution and Javert doesn't commit suicide. This is because the subjects of prostitution and suicide are considered unacceptable to depict in children's anime in Japan to the point of being taboo. Other subjects like death, poverty, illness, and even child abuse are considered fair game though, because Japan's broadcast standards are fairly lax and less restrictive compared to that of America or Canada.
Continuity Lock-Out: It's possible to understand and enjoy Little Women II: Jo's Boys without watching its predecessor Little Women although Episodes 33 and 34 has few characters from the latter.
First Installment Wins: The first few entries in the 70's such as Dog of Flanders, Rascal the Raccoon and Anne of Green Gables are mostly recognized in Japan and have the most merchandise. It helps that some of the prominent staff in Japanese animation worked on those shows such as Hayao Miyazaki and Isao Takahata.
The franchise is this as an introduction of Japanese animation in general.
It also introduced some obscure or not so well-known novels such as A Dog of Flanders, Southern Rainbow and Romeo's Blue Skies.
Germans Love David Hasselhoff: Look at the Wikipedia page for at least 60 percent of these shows in Italian, French or Arabic and they'll likely be twice as long as the language of the page you were previously reading.
Many, many French folks who were children in The '80s and the early part of The '90s remember these shows due to them being broadcast in the hugely successful morning (and afternoon) kids shows Club Dorothée and Les Minikeums.
The series also have a big support in the Philippines, where it is fondly remembered among 90's kids there along with Dragon Ball and YuYu Hakusho. Some of its popular entries have received reruns on TV to this day.
Show-wise, the most popular entries outside Japan are the ones that contain a lot of drama such as Princess Sarah, Romeo's Blue Skies and Remi, Nobody's Girl.
Glurge: According to this article, the franchise was meant for kids who grew up from late 70's to 90's, showing them the struggle that their parents and grandparents went through after World War II.
Just Here for Godzilla: The reason why many people watch Heidi, Dog of Flanders, 3000 Leagues in Search of Mother, Rascal the Raccoon and Anne of Green Gables is that Hayao Miyazaki and Isao Takahata worked on those shows.
Narm Charm: Hearing pop or rock music in some of the show's themes such as "Love with You" (Katri, Girl of the Meadows Japanese opening) and "Himawari" (Princess Sarah Japanese ending) is awesome despite that the series set in the old times.
Obscure Popularity: The franchise is well-known in Japan, Europe, Middle East and some countries in Asia but it doesn't have much mainstream recognition outside its dedicated fandom.
Pandering to the Base: One of the reasons why Nippon Animation seems nearly forgotten to foreigners nowadays is that they have been pandering more and more to its Japanese fans. If you look about the series in Japanese expect to see contents about the entries that are popular in that country, especially Rascal the Raccoon and Romeo's Blue Skies.
Periphery Demographic: The series was meant for kids and family, but over the years the series has developed quite a significant adult fanbase and there are reports where many parents encourage their children to watch them. This probably have something to do with them growing up watching those shows when they were young.
For the previously mentioned Latin-American Spanish dub of Heidi, Dragon Ball fans will recognize Cristina Carmago (Android 18 in Dragon Ball Z) as the voice of Heidi.note She also sings both the opening and ending theme songs, which also appear in at least one release of the European Spanish dub as well.
Slow-Paced Beginning: The franchise suffers from this for those people who are not interested in settings, additional back stories and characters who are not originally appeared in the novels. Each of the anime takes around few episodes to see new characters and to pick up the pacing of the plot. This is even lampshaded in the episode previews of Les Misérables: Shōjo Cosette.
Tough Act to Follow: The rest of the entries after Anne of Green Gables never managed to receive the same level of acclaim.
In terms of staff, Isao Takahata is well-known in the series thanks for directing Heidi, 3000 Leagues in Search of Mother, and Anne of Green Gables. Other directors after those shows are followed but none of them surpassed Takahata's skills.
What Do You Mean, It's for Kids?: Despite that the franchise is aimed at children and most of its entries were based on children's books, its themes and plots can be surprisingly dark and mature, such as physical abuse, war, horror and death. Many consider this to be the main draw of the franchise, as not only are most of the entries more faithful to the source material, they never dumb down, censor, or actively skirt around the darker aspects of said material, something many other foreign adaptations can't boast. It helps that Japan's censorship standards are pretty lax, so they had the freedom to actually depict said darker themes in their shows without fear of blowback from Moral Guardians.
Vindicated by History: Some of the entries that received poor ratings in their intial run tend to get this in the years following their release, usually thanks to rebroadcasts, home video sales and fansubs; the most notable examples are Remi, Nobody's Girl and Romeo's Blue Skies. The latter managed to become the second most popular WMT show according to the offcial poll by Nippon Animation in 2015.
, the franchise was meant for kids who grew up from late 70's to 90's, showing them the struggle that their parents and grandparents went through after World War II.