Interestingly, I've found a lot of parallels between early Islam and early Mormonism. Both of their leaders had similar tendencies and both were evicted from their original location where they claimed their new Zion. Though Mohammed was more successful in retaking Mecca whilst the Mormons were forced out of Missouri (1).
In no specific order:
- Prophet's with dubious histories prior to their revelation - Both given new revelations from an angel - Both claim a that the Christians or Jews had corrupted the original gospels - Focus on political power early on - Polygamy prominent among early leaders - No alcohol - Strong focus on certain forms of "purity"
I can't say whether Smith had a "dubious" history, but I'm not inclined to take this view because people think it's ok to bigoted and dismissive of the Church of LDS, and I think it's unfair.
Also polygamy was part of pre-Islamic Arabia, whereas it was contrary to custom and law in the context in which the LDS Church developed. Comparison on this point is superficial.