When Joseph Smith died, the Mormons as we know them today followed his friend Brigham Young, left Missouri and continued the church in Utah. The RLDS stayed in Missouri under Joseph Smiths wife and son. They have their temple in Independence Missouri.
Same teachings up to the point where Joseph Smith died. Then things begin to differ. They both have the Bible, Book of Mormon and the Doctrine and Covenants. However-the D/C is considered a living book that continues to be written (in both churches to this day) so what has been written since JS death is different.
The RLDS (which have since changed their name due to confusion with Mormons to "Community of Christ") church does not believe in polygamy, just as the mainstream Mormon church does not. But they do all come from the same beginnings under Joseph Smith.
On that note-KDT I would agree, very different cultures, thought not necessarily races. I recall when the RLDS church came across the quandry of having done missions into India where men had multiple wives-which went against church doctrine. So what to do what to do. They spent an inordinate amount of time discussing it and concluded that it would be abusive (their word) and dysfunctional (my word) to force men to divorce their "extra" wives in order to join the church, because it would put those women out in their society as, well, trash. Anyway, they opted instead to alter their "rules" to accept that families in that society were free to have multiple wives blah blah blah. I find it very intriguing that the battle to accept homosexuals into the fold openly -went very smoothly a few years later. Whereas accepting women into the priesthood which happened a few years prior caused a damn near 50/50 break in the church with one group leaving the community and starting another church of their own because they were so against women in the priesthood.