I was a history teacher for a few years. Frankly, I stopped looking for objective, official history long ago, when I realized how much more fun, entertaining and exciting real history is - to study and to teach. Journals and letters and unguarded communications are SO much richer than textbooks - the account of the winners' most elite element. Academicians brought us the flat-earth theory; sailors knew better for many, many years.
If you want to know what "Mormonism" really is (or was at any given time), at its most basic level, read the writings of the lay members of that time. The General Conference talks and official pronouncements tell what the global Church teaches; the various interpretations show what the local Church actually believes.
The gap is fascinating.