I’ve read the entire 21-volume Brother Cadfael series twice. Set in a 12th-century monastery and surrounding towns, it’s never too violent or horrible, and is well-written and entertaining.
The Internet Archive has multiple copies of most of these books. Whenever possible, I’ve linked to a copy that’s available for 14-day borrow.
3. Monk’s Hood
13. The Rose Rent
14. The Hermit of Eyton Forest
15. The Confession of Brother Haluin
16. A Rare Benedictine: The Advent of Brother Cadfael
20. The Holy Thief