Is Mormonism a branch of Christianity or is it a distinct religion?

[Blue3]

If Mormons aren't Protestants, then how are other Restorationist traditions Protestant?  or even Methodists?  The history of Methodism is distinct from attempts to "reform" Catholicism, after all   

 

I think Restorationist (including Mormons/LDS and Jehovah's Witnesses) should be its own branch, distinct from Catholic, Eastern Orthodox, Oriental Orthodox, and Protestantism.

[Blue3]

They don't, but they're both about apparently rejecting both Catholic Christianity and Protestant Christianity to go back to the "roots" that were revealed to them (and usually don't know as much about Orthodox churches but against them too).

[Blue3]

I would argue it is a distinct religion as they have a scriptural canon which is entirely unique to their church. Unlike simply the Bible (both Old & New Testaments) which is the sole scripture used by all Christian churches, Mormonism includes the Book of Mormon and other texts by Joseph Smith which are common to their religion but not to any other, while also using the Christian Bible. This is similar to how Christians use both the Jewish Scripture and their own New Testament which is unique to their religion. There are also many distinctive theological beliefs of the Mormons that are at odds with Christian teaching. For what it is worth Mormons do not accept non-Mormon baptism nor do non-Mormons accept Mormon baptism. This puts Mormonism and Christianity farther apart than just Catholic and Protestant churches are.

No denomination accepts other denominational baptisms, including Orthodox to Catholic or Protestant. The entire point of each Christian denomination is that they have the truth, and they alone.

This is not true. The Catholic Church accepts baptisms in any denomination that it feels has a sound Trinitarian theology, and many Protestant denominations barely even impose that condition.

I was going to say this too. Lots of Christian denominations accept baptisms from other denominations.