Even though Disney´s "Little Mermaid" was released in 1989 for the first time, Walt Disney had the idea of making an animated movie based on Christian Andersen´s fairytale already 50 years earlier.
However, the mermaid theme fascinated Walt Disney even earlier: In 1932 a short animated musical novel entitled "King Neptun" part of the "Silly Symphonies" series was produced, starring a red haired mermaid as one of the main characters, which probably layed the foundation for Ariel´s future aspect.
One of the first visual concept paintings of the actual theme of Andersen´s "Little Mermaid" were drafted by Kay Nielsen in 1941 for Disney. His works were much closer to the original story than the future movie. The character concept for the little mermaid herself however, already shows some resamblance to the finished Ariel with long floating hair and a big eyed face. Unfortunately the plans changed at that time and the concept was put on ice for a long time.
In 1985 one of Disney´s directors, Ron Clements, became interested again in adapting Andersen´s story. By coincidence he came
across the visual development work of Nielsen, which had a big influence on the future work of the animators.
The two leading animators to create the character of Ariel were Glen Keane and Mark Henn who worked before together on "Oliver & Co" and "Basil of Bakerstreet".
The first concept drawings of Ariel focus on the under water dynamics especially of her hair.
Giving the little mermaid long, floating hair as in the Nielsen concepts was no point of discussion. The under water effects of Ariel´s hair were inspired by footage of the female austronaut Sally Ride taken while she was in space.
Regarding her personality, Ariel was developed to be less melancholic than Andersen´s little mermaid, the story itself was changed to fit more to the Disney style as well. As the model for Ariel´s appearance, like the facial and body features, the young actress Alyssa Milano was chosen.
Passion, desire and also willingsness to make sacrifices for love were atributes the animators borrowed from the original Andersen storybook for Ariel. Seemingly they also wanted her to have an adventurous and a somewhat undutyful nature of a typical teenage girl.
Apparently, the development of the physical aspect of Ariel was also inpired by the mermaid characters created by Fred Moore for "Peter Pan" in 1953. Not only the face, with big, less realistic shaped eyes, but also Ariel´s signature seashellscould already been found in Moore´s mermaids before.
But while Moore´s mermaids were alluring and touchy, the little mermaid was considered to be innocent and endearing.
Ariel´s character got a more childlike curiousness which reflects in her facial features. Nevertheless, Keane obviously didn´t want Ariel to look like a child and gave her a curvy womanly body.
By coloring Ariel´s hair in firy-red, the animators made her stand out of the rest of the merfolk. This could already been seen in the "King Neptune" short. Moreover, this coloration also builds a contrast to the blueish sea world she feels not to belong to.
During the development process the character proportions got improved and the details as well as facial expressions were finalized.
Even though Ariel´s aspect may be less realistic than earlier animated female characters (e.g. Cinderella and Aurora), to create a realism in movement and mimics, most of the scenes were filmed with live actors. This technique was laso used in the earlier princess movies. Ariel was performed by Sherri Lynn Stoner and Jodi Benson.
The Little Mermaid was the last Disney feature film to use the traditional handdrawn and handpainted cel method requirering a multiplane camera.
After that, Disney studios used the "Computer Animation Production System" developed by Pixar until now.
Ariel´s film is the last full-length animation picture drawn and colored manually, and maybe this is one of the reasons, why "The Little Mermaid" still spreads Walt Disney´s magic equally to the earlier masterpieces.