The Mormon colonies in Mexico are settlements located near the Sierra Madre mountains in northern Mexico which were built by members of The Church of Jesus Christ of Latter-day Saints beginning in 1885. Many of the original colonists came to Mexico in order to escape prosecution for the Mormon practice of plural marriage in the United States. The towns making up the colonies were originally situated in the states of Chihuahua and Sonora, and were all within roughly 200 miles of the US border. By the early 20th century, many of these had reached a high degree of prosperity and cultural refinement. However, in the summer of 1912, the colonies were evacuated due to the anti-American violence incident to the Mexican Revolution and many of their citizens left for the United States and never returned. Some Latter-day Saints did eventually return to their property, but today only Colonia Juárez and Colonia Dublan in the Casas Grandes river valley remain active settlements. The Colonia Juárez Chihuahua México Temple, built in 1999, is located in Colonia Juárez, and is currently the smallest temple the LDS Church operates.
Taylor continued Young's policy of missionary work in Mexico, and through the early 1880s colonization was considered on several occasions without effort to begin the process. However, in 1882, the Edmunds Act was passed by the United States Congress. This was part of the by then 20 year struggle by the US government to curb the LDS practice of plural marriage in Utah Territory and other locations in the American West. Among other things, the law felonized the practice of polygamy and disenfranchised polygamists. As a result, over a thousand Latter-day Saint men and women were eventually fined and jailed. Some sent as far away as Michigan to fulfill their terms.
Many Mormon settlements in the United States are in areas that at one time belonged to Mexico, but nearly all of these were already part of the United States at the time of settlement. The exception is Salt Lake City itself, which was settled in the spring of 1847 and became part of the U.S. in 1848.