Well I’ve ready the below books and can recommend them all if you’ve more than a passing interest in the topic.
loyalists by Peter Taylor , If your interested in that aspect of it , heavy paramilitary leaning . A mirror book to Taylor’s republican book.
the people with no name by Patrick griffin, a very scholarly book , i got mine from the British library in London when I was working there , ( don’t ask ) get it for 25 quid eBay , a good read and the title is taken from the fact that in America they were labelled as Irish , when they have struggled to not be Irish , most of their