Cover art
Green, Roland J., and John F. Carr. Great Kings' War. Ace 1985 (cover art by Alan Gutierrez).
Cover art
Carr, John F. Kalvan Kingmaker. Pequod 2004.
Cover art
Carr, John F. Siege of Tarr-Hostigos. Pequod 2004.

Carr, John F., and Roland J. Green. Lord Kalvan of Otherwhen
Series note: A series of sequels to the original Lord Kalvan of Otherwhen, by H. Beam Piper, q.v., which was a novel-length Paratime story. Includes Carr and Green's Great Kings' War, Carr's Kalvan Kingmaker, Carr's Siege of Tarr-Hostigos, Carr's The Fireseed Wars, and Carr's Gunpowder God.
Web link: Hostigos.com

Carr, John F., and Roland J. Green. Great Kings' War
Divergence: c 2000 BCE
Summary: In their first attack on Lord (now King) Kalvan, Styphon's House hits him with three forces, but is defeated in all cases.
Series note: First sequel to H. Beam Piper's Lord Kalvan of Otherwhen, q.v.
Published: Ace 1985 (0441302009BUY), as by Green and Carr.
— Revised edition, as by Green and Carr, posted on-line at Baen Free Library, Oct. 1, 2004.
— Revised and expanded edition, as by Carr and Green, Pequod 2006 (0937912034BUY).
Web link: Baen Free Library

Carr, John F. Kalvan Kingmaker
Divergence: c 2000 BCE
Summary: Styphon's House drives barbarians from the North American plains east into Kalvan's territory in order to destroy him, but he turns the tables on them.
Series note: Second sequel to H. Beam Piper's Lord Kalvan of Otherwhen, q.v., following after Great Kings' War.
Published: Pequod 2001 (0937912018BUY).
— Expanded from "Kalvan Kingmaker", as by Carr and Roland J. Green, in Alternatives (eds. Robert Adams and Pamela Crippen Adams), q.v.

Carr, John F. Siege of Tarr-Hostigos
Divergence: c 2000 BCE
Summary: Lord Kalvan loses his citadel to the forces of Styphon's House.
Series note: Third sequel to H. Beam Piper's Lord Kalvan of Otherwhen, q.v.
Published: Pequod 2004 (0937912026BUY), rev. 2012.
— Expanded from "Siege at Tarr-Hostigos", as by Roland J. Green and Carr, in There Will Be War 8: Armageddon (eds. Jerry Pournelle and John F. Carr), Tor 1989 (0812549651BUY).

Carr, John F. The Fireseed Wars
Divergence: c 2000 BCE
Series note: Fourth sequel to H. Beam Piper's Lord Kalvan of Otherwhen, q.v.
Published: Pequod 2010.
Publication note: Known during development by various titles, including Queen Rylla's Crown, Queens Rylla's Victory, and Queen Rylla's Throne. May have briefly been called Gunpowder God; if so, that title was later re-applied to the next book in the series.

Carr, John F. Gunpowder God
Divergence: c 2000 BCE
Series note: Fifth sequel to H. Beam Piper's Lord Kalvan of Otherwhen, q.v.
Published: Pequod 2012.
Publication note: Note that "Gunpowder God" was the title of the novella which made up the first half of Lord Kalvan of Otherwhen, q.v., and which was used as the title for one British edition of Lord Kalvan.