According to BoxRec, Boxing's Official Record Keeper, Willard Bean, was never a World Champion Boxer and he never boxed in St. Louis as depicted in the movie. He had two matches outside of Utah; one in San Fransisco, California and one in Denver, Colorado. His professional boxing record was: 18 bouts and 181 rounds. 8 wins (7 by knockout), 5 losses (1 by knockout) and 3 draws.
At the end of the movie it is said that all four of Willard's and Rebecca's children were valedictorians of their respective graduation classes. This is not true; only two were valedictorians.
Four missionaries come to the house. Two are introduced as Elder Crawford Gates and Elder Gordon Hinckley. Latter-day Saints will recognize those names: Gates was a prominent composer and Hinckley was the Latter-day Saint Prophet from 1995 to 2008. The scene in the movie takes place around 1920 - 1922. Gates was born in 1921 and Hinckley in 1910; Gates would have been one year old and Hinckley 11 or 12 years old.