He is best known for his Sparrowhawk series of novels, set in England and Virginia before the American Revolutionary War. His other fiction includes one suspense series (featuring American entrepreneur Merritt Fury), one contemporary detective series (featuring Chess Hanrahan, who solves paradoxical murders), and one period detective series (featuring Cyrus Skeen in Nineteen Twenties San Francisco).
Cline has also written on freedom of speech and censorship issues for The Encyclopedia of Library and Information Science and The Journal of Information Ethics. He has written numerous feature and cover stories, as well as book reviews, for Marine Corps League Magazine, The Colonial Williamsburg Journal, The Wall Street Journal, and The Intellectual Activist. His article on English political philosopher John Locke was carried in two editions of Western Civilization (McGraw-Hill). His Sparrowhawk historical series is being used in college, high school and middle school literature courses around the U.S., and has a significant foreign following as well, particularly in the United Kingdom.
Outside of his work as a novelist, Cline is known for his writings on aesthetics, his defense of capitalism and of free speech, and his criticism of contemporary political trends, and of Islam (and religion in general).
As the author of the Sparrowhawk series of novels, published by MacAdam/Cage Publishing of San Francisco since 2001, Cline has reclaimed the publication rights to that series, in print and e-book formats, because the California Secretary of State's records show that the company is no longer in business.The series in both formats is now published under the Patrick Henry Press imprint.
As a writer, his strongest influence has been novelist-philosopher Ayn Rand.
He has been a guest commentator for Rule of Reason at the Center for the Advancement of Capitalism since 2006. His numerous columns have also appeared on Capitalism Magazine, Family Security Matters, and other blog sites.
In December 2013, MacAdam/Cage, Publisher, the original publisher of the Sparrowhawk historical series, declared bankruptcy. Titles of the series had not been reprinted, nor vendor orders filled, by MacAdam/Cage for about two years. All of the Sparrowhawk titles have since been republished by the Patrick Henry Press as print books or on Amazon Kindle. The two detective series, and one suspense series are also on Amazon Kindle.
- First Prize, Mysterious Press/Warner Book, 1988, ISBN 0-89296-291-7
- Whisper the Guns, Atlantean Press, 1992, ISBN 0-9626854-2-9
- Whisper the Guns, Patrick Henry Press, 2011, ISBN 978-1481220880
- Sparrowhawk One: Jack Frake, MacAdam/Cage Publishing, 2001, ISBN 1-931561-00-1
- Sparrowhawk Two: Hugh Kenrick MacAdam/Cage Publishing, 2002 ISBN 1-931561-20-6
- Sparrowhawk Three: Caxton, MacAdam/Cage Publishing, 2004, ISBN 1-931561-53-2
- Sparrowhawk Four: Empire, MacAdam/Cage Publishing, 2004, ISBN 1-931561-87-7
- Sparrowhawk Five: Revolution, MacAdam/Cage, 2005, ISBN 1-59692-154-4
- Sparrowhawk Six: War, MacAdam/Cage, 16 January 2007, ISBN 1-59692-198-6
- Sparrowhawk Companion, MacAdam/Cage, 2008, ISBN 978-1-59692-261-7 (in collaboration with Jena Trammell, editor)
- Presence of Mind, Perfect Crime Books, 2010, ISBN 978-0-9825157-0-9
- Honors Due, Perfect Crime Books, 2011, ISBN 978-1-935797-14-2
- First Prize, Perfect Crime Books, 2010, ISBN 978-0-9825157-7-8
- With Distinction, Perfect Crime Books, 2012, ISBN 978-1-935797-21-0
- Run From Judgment, Patrick Henry Press, 2012, ISBN 978-148-1248709
- We Three Kings, Patrick Henry Press, 2012, ISBN 978-1481219075
- China Basin, Patrick Henry Press, 2012, ISBN 978-1481182201
- The Head of Athena, Patrick Henry Press, 2012, ISBN 978-1481202466
- The Daedâlus Conspiracy, Patrick Henry Press, 2012, ISBN 978-1481208772
- The Chameleon, Patrick Henry Press, 2012, ISBN 978-1481212625
- A Crimson Overture, Patrick Henry Press, 2013, ISBN 978-1492251972
- The Black Stone, Patrick Henry Press, 2014, ISBN 978-1494974626
- Running Out My Guns, Patrick Henry Press, 2012, ISBN 978-1481810067
- Broadsides in the War of Ideas, Patrick Henry Press, 2012, ISBN 978-1481800792
- Corsairs and Freebooters, Patrick Henry Press, 2012, ISBN 978-1481804509
- Boarding Parties & Grappling Hooks, Patrick Henry Press, 2013, ISBN 978-1482087833
- Letters of Marque, Patrick Henry Press, 2013, ISBN 978-1493749034
- From The Crow's Nest, Patrick Henry Press, 2014, ISBN 978-1499690620
- The Pickwick Affair, Patrick Henry Press, 2014, ISBN 978-1500217167
- Edward Cline's website
- Edward Cline's articles at Capitalism Magazine
- "Interview with novelist, Ed Cline, author of Sparrowhawk Series", Egoist, 2008 11 21