Jon Krakauer has written several books which rightly deserve consideration as the best of the best. He has explored the inner workings of humanity through the prism of extreme mountaineering (Into Thin Air) and a personal journey of self discovery (Into the Wild) but no book he has written is as powerful as his insightful look into extreme religion (Under the Banner of Heaven).
For thousands of years man has sought to redeem irredeemable actions through religious principles - Krakauer chooses to focus on the Mormon church in his book yet the text works to illuminate the base qualities of all religion. Essentially, as he boils it down, religon has dominated our world for so long it demands closer attention be paid to what we believe - it is our duty to examine the basic tenants of faith. Mormonism has two different doctorines (those who believe in Polygamy and those who do not) and is ripe for such a close, detailed look. The church was born from violent circumstances and Krakauer does not shy away from these bloody origins.
However, as most people know, a deep examination of the origins of any faith (especially one which started less than 200 years ago) reveals significant cracks in the foundation. This is true of Mormonism as everything believed by the faithful can be cut down to what the prophet Joseph Smith saw in a hat. At some points during reading the book, one may stop and nearly shout "How can people buy this?" but the simple fact is - more than twenty million people do. Mormonism is one of the fastest growing religions in the world.
The history of Mormonism is intersperced with the brutal murder of Brenda Lafferty and her daughter Erica by her husband Ron and his brother Dan. Ron would later claim God told him to murder her as she had been corrupted by the devil (both brothers are currently in prison for the forseeable future - Ron sits on death row). The use of faith to "justify" murder is just one black mark in the long and violent history of the religon which has been shrouded for the most part in darkness. Polygimist leaders have built communities and ridiculously guarded compounds to protect what they see as their fundamental rights.
Yet, while Krakauer's illuminating look at religion succeeds he also does what would have seemed impossible - he makes the history of the Mormon church ridiculously entertaining. You literally cannot put this book down. His writing, always one of his strongest suits, is on full display here. While he informs and enlightens he also creates a page turner. Not many authors could have succeeded in this regard.
Naturally, this book has been condemned in many religious circles rather unfairly. Krakauer portrays the facts in a straightforward and non-biased manner. Plus, if you believe in what your religious leaders tell you, why should it matter what other people think of your religion? Ultimately any close look at faith will inevitably cause the cracks to show but is this not a good thing? Questioning the workings of our world and not just blindly accepting what we have been told has made us great, and this book helps to remind us of the need to do just that.