Development Screenwriter Elana Lesser recalled first hearing the story of
Balto from her grandfather as a child, and as an adult, decided that it would make an excellent animated and live-action film. She and her husband, fellow screenwriter Cliff Ruby, pitched a screenplay to
Amblin Entertainment in
Universal City, California, and executives
Douglas Wood and Bonne Radford relayed it to co-directors
Phil Nibbelink and
Simon Wells at Amblin's
London-based animation studio,
Amblimation.
Steven Spielberg agreed that the story had potential, but he was initially concerned that such a film would not be colorful enough. To reassure Spielberg, Wells showed him several color studies by production designer Hans Bacher, which showed that the film would not simply depict black and white dogs against desolate scenery. Nibbelink and Wells had initially developed
Balto together, before Nibbelink left to continue working on ''
We're Back! A Dinosaur's Story'' (1993), and screenwriters
Roger S. H. Schulman and David Steven Cohen, and several uncredited writers, further developed the script. To source the dogs'
character animation, the filmmakers set up special drawing classes with about seven
Siberian Huskies and videotaped them walking around the studio, while the animators studied their movements and anatomy. During these classes,
Kristof Serrand, who was assigned to supervise the animation on Boris, gave a lecture on the
locomotion of dogs. Former
Disney animator
Jeffrey J. Varab, who had trained under
Eric Larson and joined Amblimation during production on ''We're Back!'', was assigned to co-supervise the animation on Balto alongside Dick Zondag. At Wells's behest, Varab lectured about dog anatomy and Balto's drawings, based on his work on
The Fox and the Hound (1981), and citing preliminary
character sketches drawn by character designer
Carlos Grangel and original
model sheets of Tramp from
Lady and the Tramp (1955). Prior to his departure from the project, Nibbelink lectured on applying spacing and weight to the dog animation, using the "bouncing ball" animation exercise he had learned from
Frank Thomas while working as an animator at Disney alongside Varab. Wells and several other crew members took special trips to
Finland to study
dog sledding. Principal animation lasted from 1993 to 1994, with each animator completing five seconds of animation a week on average; Ken Keys, one of the animators on Steele, stated that he was "throwing away nine drawings to keep one". The film is mainly
hand-drawn, but with considerable
computer animation in more challenging visual elements; all of the falling snow was animated using an early CGI
particle system. Additional animation was provided by the Danish studio
A. Film Production. Each shot was
composited digitally and transferred to film through a "Solitaire"
film recorder, before being spliced into the leica reel. According to Bacon, "It was very hard. I didn't like it. They would play his dialogue in the way that he had said it in my head right before I'd say my line." Wells said he "did a terrific job and was really enthusiastic".
Jennifer Blanc also originally voiced Jenna, but she was also subsequently replaced by
Bridget Fonda. Fonda explained in an interview with
Bobbie Wygant that she was offered the role of Jenna via phone call, and accepted after being shown a
rough cut on tape, which showed some shots in finished form, some still in pencil test form, and some missing. When asked how hard it was to be doing voice-over work for animation for the first time, she explained, "It was odd, it was different. It was challenging. It was exhausting in that I had to be more active, and more outgoing vocally than usually. And syncing up to animated is very difficult. But, y'know, it was just so imaginative, and satisfying in a different way."
Bob Hoskins voiced Boris, having previously collaborated with Spielberg on
Who Framed Roger Rabbit (1988) and
Hook (1991). Wells stated that his performance helped shape Boris, praising it as "a lot more emotional and effusive than we had originally conceived the character to be". Wells recalled Hoskins's brief struggle with Boris's accent and angrily venting that he "used to have a career [before] playing a goose". In his autobiography,
Jack Angel stated that he, Danny Mann, and
Robbie Rist were flown to London to record their respective roles as Nikki, Kaltag, and Star together, and he brought his wife, Arlene Thornton. Angel added that even though they had no personal interaction with Spielberg, he flew Angel, Mann, and Rist out again after they had finished recording their roles, because "somebody apparently didn't get it right the first time".
Live-action segments Screenwriter Frank Deese, who was already writing a script draft for
Small Soldiers (1998) that Amblin later rejected, was hired by Radford to script the live-action prologue and epilogue segments in 1994, though he received no credit in the finished film. The two segments were filmed on-location in
Central Park later that year, over a period of one to two days. Closing down the area for filming proved to be a challenge, due to uncooperative locals. However, Wells greatly enjoyed working with
Miriam Margolyes, and was impressed with how well she worked with Lola Bates-Campbell, who played Rosy's granddaughter. Horner also collaborated with songwriting duo
Barry Mann and
Cynthia Weil to write an original song, "Reach for the Light", sung by
Steve Winwood, which plays over the film's end credits. It was initially reported that the end credits would feature a song co-written by
Neil Diamond and
Carole Bayer-Sager, but this song never materialized. ==Release==