I recently listened to the AskHistorians podcast about Buddhism in Tibet and Bhutan, and the rise and machinations of people like Pagsam Wangpo and Ngawang Namgyal. I found this endlessly fascinating, particularly the way theological justification was given for things like resolving successions and inheritance, and the way Buddhism wove itself into the political systems of the area at the time.
I want to know more about the history of political Buddhism, if such a phrase can be used, but I don't know where to look to find good sources. To clarify, my interest doesn't stop at the Himalayan region; for instance, I'm also aware that Buddhism was a big deal for the political climate of Japan in the first millennium, and very much interested in knowing more about that, too, as well as similar history as it concerns other parts of East Asia. What are some good sources that are reasonably accessible to someone who is not a historian and lacks access to university libraries and the like?
Hi there! I was the interviewee for that episode and I'd recommend if you're interested in Tibet and Bhutan further, to take a look at the https://www.reddit.com/r/AskHistorians/wiki/books/innerasia#wiki_tibet_and_bhutan
Buddhism has always been mildly political. Remember that even in the earliest retellings of the Buddha's life, he was born a Prince who rejected his fate as a world-conqueror. Wherever it spread to, it also became ingrained with local and eventually national politics.
I don't know of any books that deal strictly with the relationship between Buddhism (at large) and politics (at large). (Though that doesn't mean they don't exist, they just haven't come across my radar.) One possibility might be A Very Short Introduction to Buddhist Ethics by Damien Keown. But that would only exacerbate the point that you'd have to look at a specific area, teaching, or lineage to find a work of any real authority.
I can list a few examples that would show the difficulty of this process:
The myriad differences in local histories, cultures, and economies make it difficult to make any sort of blanket statement about Buddhism and politics. In 1392, the Yi Dynasty came to power in Joseon Korea and immediately expelled the Buddhists from positions of power, relegating the Koreans to the mountains where they could do less social damage (as the Joseon court saw it). In Tibet or Bhutan, such a thing was virtually impossible, but that doesn't mean there wasn't room for various sects to try to gain power over the other, as was discussed in the podcast.
If you pick a country, it'd be easier to narrow down its relationship with government and Buddhism. Right now I'm reading Tibetan Nation by Warren W. Smith. It's a pretty comprehensive history of Tibet and the origins of the Tibetan ethny and national identity, which is impossible to discuss without constantly discussing Buddhism. I'm also reading A History of Tibet by the Fifth Dalai Lama (trans. Zahiruddin Ahmad). As a book written by a monk, it's not hard to see where Buddhism might make an appearance (i.e. everywhere). Chapter 1 Part 2 is titled "The Life of the Buddha." In other words: before HHDL5 talks about the country he rules, he recounts the life of Siddhartha Gautama. (Are there any histories of Italy that start with the life of Jesus?)
I also just finished Samuel Hawley's The Imjin War which discussed a topic that has been a bit of an obsession for me: how did Korean monks, after being persecuted for centuries, suddenly rise up to fight the Japanese, (at the request of the Korean King!)? Did Seosan/Hyujong feel any remorse at breaking his Vinaya vows to fight Hideyoshi's aggression?
Buddhism has a 2,500 year history. It's experience is tied intimately with the cultures that founded it. The experience of Japanese warrior monks who fought with Oda Nobunaga in the 1500s, is entirely different from those Buddhists who ruled and managed entire Kingdoms in the Himalayas, or protestors who continue to fight against the dictatorship in Burma/Myanmar.
It'd be best to start looking at certain countries and eras for better understanding and suggestions.