How to Plan a Crusade

How to Plan a Crusade: Religious War in the High Middle Ages
By Christopher Tyerman
Published in October 2017
432 Pages
Thibault’s Score: 3/5

My thoughts on this book can be summarized in four words:

Fascinating topic; mediocre execution.

The book advertises itself as focusing on the details of how leaders planned, financed, and executed crusades. The problem is that only roughly half of the book actually covers this topic; and the other half goes into semi-relevant side topics. The author is further hampered by an annoying academic writing style artificially inserts “big word fluff,” rather than focusing on clarity and concrete details.

More than half of the book covers the ideological, psychological, religious, cultural, and social aspects of crusade planning. I found this frustrating, as many books already cover this when discussing the crusades. The truly unique parts of the book which focused on the details of financing, recruitment, transportation, and logistics were completely buried.

The book was also not written for the right reasons. The author focused on trying to prove the obvious: that medieval people were rational actors. His reason for covering the planning of the crusades is to prove this pedantic point. Only uneducated boomers who got all of their information from 1980s movies believe this. It is a very dated stereotype that doesn’t even need to be mentioned. For a younger reader like me, who never saw medieval people as irrational, the constant rehashing of this argument was very annoying and distracting. Instead, I wish that rather than telling the reader “why” this book is important; he just focused on the “what” and let the reader decide that for themselves.

I think that part of the reason for the focus on the mental rather than physical aspects is because writing about the granular specifics is much more difficult. The written sources tend to cover the ideology; and so does Tyerman. A true discussion of granular military logistics and economics would require more inference from non crusade sources; and more archeology. Instead of writing the book that readers like me who already know about the crusades were all hoping to read; he wrote the book that was easy to write.

In my book reviews, I usually try to list some of the interesting things that I learned. However, the writing style was so distracting, and the information so generic, that I can’ t remember if individual facts I know about crusades planning came from this book or from other sources.

Here is an example. Tyerman spends many pages proving that crusaders used accounting techniques. He gives quote after quote after quote from primary sources proving that knights knew and cared about accounting. To someone like me, this is completely obvious and at most merits a paragraph. What I was burning to know was the specific details of what the accounts look like, how the accounting was executed, etc… He never covers these details, and instead moves onto the next topic.

Likewise, he has many pages where he proves that there was debt financing of crusading activity. Once more, to anyone who knows even the basics like me, this is obvious. What I really wanted to know was who was doing the lending, where the money lent came from, what the interest rates were, what the terms of the agreements look like, etc… He never covers this. What is worse is that I have done a little bit of this research myself, and I know that at least for the doomed fourth crusade there is at least some evidence for what this might have looked like in practice.


Tyerman could not have picked a more interesting topic for this book. But I still do not recommend it. This book was way too deep and in the weeds when it came to things like justifying the crusades; but frustratingly vague when it came to military logistics or economics. This book will be too hard for novices; but frustrating for anyone who wants a more in depth view. This book has no audience.

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