Stumbled across Nabil-i-A'zam's Dawn-Breakers:
Nabil's Narrative of the Early Days of the Baha'i Revelation, while I was looking for maps. This was originally written in Persian, 1932. Though it looks like it was translated in the 70's. You can look through the book here chapter by chapter, seems as if you can absorb as little of or as many sections as you like, for free!?