Justin Morgan Had a Horse was a 1972 Walt Disney film, based on a 1945 historical novel of the same name. That novel was based on Justin Morgan, who indeed had a horse.
Justin Morgan had a spectacular and versatile colt who became the sire of a celebrated American breed: the Morgan Horse. But Justin Morgan was more than any old horse breeder; he taught singing and composed hymns and fuguing tunes.
One hymn in particular has cemented his musical reputation. A hymn written from personal tragedy: the hymn, "Amanda," written after the death of his wife.
Composer Thomas Canning a professor at the Eastman School, took that sad and lovely Justin Morgan hymn and wove it into a fantasy for orchestra that became his signature.