Some of my favourites where novels based on history, like Gates of Fire, Steven Pressfield, (about the battle of Thermopylae this was long before they made 300) also read his Tides of War (about Alcibiades). I also enjoyed a biography on Cleopatra and Warriors of God, Richard the Lionheart and Saladin (the third Crusade) was by James Reston. Oh almost forgot to mention Amazulu by Walton Golighty (about King Shaka and his Zulu warriors). Also read about Attila the Hun think the book was called Sword of Attila... was good but not great.
https://www.goodreads.com/book/show/1285191.The_Albigensian_Crusade Possibly made better for me because I love this part of Europe, riding around the Pyrenees on a motorbike and visiting the Cathar strongholds is my idea of a good holiday.