Historians now say they have identified the source material for about 75% of The Book of Mormon. They contend that Joseph Smith wrote the BoM using these sources. The remaining 25% they have not yet identified. This thread is to focus in on the sources of the 75%.
One of the biggest sources (about 25% according to LDS historian Grant Palmer) is the 1769 edition of the King James bible. Joseph used stories, motifs, verses, and entire chapters from the KJV when he wrote the BoM. Joseph would change the character names and places, but use the same stories. In addition, even modern translation errors from the KJV appear in the BoM. (One would think that if the BoM was truly translated from ancient golden plates, there wouldn’t be the same modern translation errors as seen in the KJV).
Besides the bible, Joseph included a great deal of evangelical Protestant concepts, practices, and exhortations (particularly Methodist) in the BoM. These are ideas he got from his own backyard, from sources such as revivals, meetings, etc. The preachers in the BoM are exactly what Joseph encountered at Methodist revivals. He also incorporated the war strategies from the war of 1812 and the Indian wars into the BoM. Furthermore, he used ideas from his own family life experiences, particularly his own father’s dreams.
This list is not exhaustive, but is a good start. In future posts we can discuss specific examples.