Start with high-confidence tudor & elizabethan britain books, then narrow by subgenre or adjacent topics.
In Search of a Kingdom
Laurence Bergreen, Michael Page
The Scapegoat
Lucy Hughes-Hallett, Harper
Boleyn Traitor
Philippa Gregory
Lady in Waiting
Anne Glenconner, Grand Central Publishing
In Shakespeare's Shadow
Michael Blanding
Mary Queen of Scots
Antonia Fraser
Tyrant
Stephen Greenblatt
Dark Renaissance
Thomas of Woodstock
Peter Corbin, Douglas Sedge
The Other Boleyn Girl
Vanessa Kirby, Philippa Gregory
The Boleyn Inheritance
Georgia Maguire, Pippa Bennett-Warner
Queens of the Conquest
Alison Weir, Julia Franklin
Queens at War
Alison Weir
Game of Queens
Sarah Gristwood
Shakespeare's Greatest Love
David Medina
The Six Loves of James I
Mr. Gareth Russell, Gareth Russell
The Troublesome Reign of John, King of England
Charles R. Forker
The Eagle and the Hart
Helen Castor
Fatal Throne: the Wives of Henry VIII Tell All
M. T. Anderson, Candace Fleming