My knowledge of Edward I isn't extensive so I can't comment on the accuracy but it is well written and managed to suck me in. I sat down only planning to read the first chapter as I had to get up early for work and ended up reading 100 pages. I haven't got to his actual kingship yet, but what I have read about his early life is very interesting so far, so many cases of faction hopping and double crossings.
It's called "A Great and Terrible King", by Marc Morris.
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