All good books, I've read many of the above - I envy those that haven't read Patrick O'Brian yet, you have such a 20 novels treat awaiting you.
Robert Graves is something of a supremo when it comes to dramatised historical fiction and I would recommend 'Wife to Mr.Milton: the story of Marie Powell' as one of the most detailed insights into the events that led up to the execution of Charles I. Marie Powell was the wife of John Milton who wrote the epic poem Paradise Lost. It is the most amazing reconstruction of life in that pre-civil war period of early to mid 17th century London I've come across (a period that is a particular favourite of mine when it comes to historical fiction, encompassing as it does the execution of the Monarch, the English Civil War, the Great Plague and the Fire of London rounding out with the Restoration of Charles II finally ushering England, belatedly, into renaissance).