Start with high-confidence ancient civilizations books, then narrow by subgenre or adjacent topics.
Magic Tree House Books 1-4 Boxed Set
Mary Pope Osborne, Sal Murdocca
Time Lions and the Chrono-loop
Krystal Sutherland, Martin Seneviratne
Percy Jackson and the Olympians: the Lightning Thief the Graphic Novel
Rick Riordan, Robert Venditti
The Wolf-girl, the Greeks, and the Gods: a Tale of the Persian Wars
Tom Holland, JASON COCKCROFT
