* The Unforgiving Minutes (1995)
* The Second Life (1998)
* The Tenant of Wildfell Hall (1999)
* The Eternal Lover (2001)
* The Queen's Folly (2003)
* Emperor (2006)
* The Accidental Fortune (2008)
* The 13th Tribe (2011)
* King's Wrath (2013)
* Assassin's Run (2015)
* The Spy's Revenge (2017)
* The Traitor's Gamble (2019)
* The Assassin's Curse (2021)
Non-Fiction
* The Great Irish Potato Famine (2007)
* The Last Duel: A True Story of Crime, Scandal, and Trial by Combat in Medieval France (2004)
* The People's History of Ireland: A Thousand Years of Struggle and Resistance (2011)