There are six books, about a rich kid and a poor kid from Bristol in the UK, who meet in grammar school and become lifelong friends. They were both born in 1920, so we get to see how they and their families and friends are effected by the Depression, WWII, the Cold War, and even the depredations of Margaret Thatcher. (Spoiler alert - Archer is a former conservative member of Parliament, so he is quite complimentary to the Iron Lady. However, one of the major characters supports the Labour Party, so you actually get a fairly balanced picture of British politics.)
I devoured the books! And when I finished the last one, I just cried and cried - great big, cathartic tears.
The books are Only Time Will Tell (2011), The Sins of the Father (2012), Best Kept Secret (2013), Be Careful What You Wish For (2014), Mightier Than the Sword (2015), Cometh The Hour (2016), and This Was a Man (2016). They should definitely be read in order.
(One of the characters becomes an author of a series of detective novels, starring a character named William Warwick, who just happens to be the main character of Archer's latest book series! The first two books are Nothing Ventured (2019), and Hidden in Plain Sight (2020), with a third coming in April of this year. I also recommend these!)
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