- Spartacus Educational - publishes books on British and U.S. history.
- Everton Publishers - genealogical magazine.
- Cultural Relics Publishing House - publisher of books on antique Chinese relics and archaeology.
- Osprey Publishing - publishes and sells military history and military aviation books, including series such as Men-at-Arms, Campaign, New Vanguard, Warrior, and Aircraft of the Aces.
- Online Originals - publishes book-length works by new and established authors, and sponsors a live literary soirée at a French château.
- Heritage Books, Inc -
- GeoHistory - devoted to multi-media electronic publishing of world history content.
- Oxbow Books - sellers and publishers of archaeology, classics, and medieval titles. Also provides information on the David Brown Book Company.
- Oak Knoll Books - specializes in out-of-print books about book collecting, book history and the book arts; publisher, distributor, and bookseller.
- HarpWeek - electronic index of 19th century history, literature, advertising, society, and culture, as found in the publication Harper's Weekly.