Apparently the Mormon Church had a “one drop” policy until they expanded into Latin America. Too many of those mulattoes didn’t know they were supposed to be “black” and the “white” Mormons weren’t about to press the issue. So, their Prophet had a “revelation” from God. This article doesn’t emphasize that fact but I have read some scholarly works that DO emphasize it.
Some blacks say Mormon Church must address racism
by Debbie Hummel, Associated Press, 6/6/2003