In the medieval Europe, the official language was Latin, because it was found everyone, so this was the language that was not vernacular.
You can’t just search it up on the internet?
The Church of Jesus Christ of Latter Day Saints was founded by Joseph Smith. The religion is based off of the scripture translated by Joseph Smith, The Book of Mormon which is used in conjunction with The Holy Bible and The New Testament. A Christian religion, the LDS church believes in following the teachings of Jesus Christ.