The
Fundamentalist Church of Jesus Christ of Latter-Day Saints (
FLDS Church) is one of the largest
Mormon fundamentalist denominations and one of the largest organizations in the United States whose members practice
polygyny. The FLDS Church emerged in the early twentieth century when its founding members left
The Church of Jesus Christ of Latter-day Saints (LDS Church). The split occurred largely because of the LDS Church's suspension of the practice of
polygamy and its decision to
excommunicate its members who would continue the practice.