* The Devil's Marchioness (1990)
* Nightshade: City of the Dead (1995)
* The Great Ordeal: A Tale of the Crusades (1997)
* The Medici Devil: A Novel (2000)
* The King's Vengeance (2002)
* Shadow of Time (2004)
* The Queen's Justice (2006)
* The Empire's Fury (2008)
* The Warrior's Return (2010)
* The Lost Throne (2012)
Nonfiction:
* The History of the Crusades (1998)
* 100 Great Historical Sites: From the Colosseum to the Taj Mahal (2000)
* The History of the Renaissance (2002)
* The History of the Reformation (2004)
* The History of the French Revolution (2006)
* The History of the American Revolution (2008)
* The History of the Civil War (2010)
* The History of World War I (2012)
* The History of World War II (2014)
Short Stories:
* "The Shadow of Time" (1996)
* "The Queen's Justice" (2005)
* "The Empire's Fury" (2007)
* "The Warrior's Return" (2009)
* "The Lost Throne" (2011)
Essays and Articles:
* "The Crusades: A Holy War" (1999)
* "The Renaissance: A Time of Rebirth" (2001)
* "The Reformation: A Time of Change" (2003)
* "The French Revolution: A Time of Terror" (2005)
* "The American Revolution: A Time of Liberty" (2007)
* "The Civil War: A Time of Division" (2009)
* "World War I: A Time of Conflict" (2011)
* "World War II: A Time of Crisis" (2013)