Start with high-confidence christian historical stories books, then narrow by subgenre or adjacent topics.
The Judge of God
Gary Martin
Attack at Pearl Harbor
Nancy LeSourd
Secrets of Civil War Spies
Escape on the Underground Railroad
Adventures in Jamestown
The Prophet, the Shepherd and the Star
Jenny L. Cote
The Wind, the Road and the Way
The Fire, the Revelation and the Fall
Voyage With the Vikings
Paul McCusker, Marianne Hering
Hunt for the Devil's Dragon
Marianne Hering, Wayne Batson
The Redcoats Are Coming!
Marianne Hering, Nancy I. Sanders
The Story of Rolf and the Viking Bow
Allen French
