Cover art
Harrison, Harry, and John Holm. The Hammer and the Cross. Tor 1993 (cover art by Kevin Johnson).

Harrison, Harry, and John Holm. Hammer and the Cross Trilogy
What if: In the seventh century CE, a new religion known as the "Way of Asgard" gained foothold in northern Europe, promoting Nordic traditions in an organized church.
Series note: A series consisting of The Hammer and the Cross, One King's Way, and King and Emperor. The first two books may be found in an omnibus volume entitled Warriors of the Way.
Comments: On many editions in this series, Holm (a pseudonym for Tom Shippey, q.v.) is not given cover credit.
Original in: English.
Translation: German as Hammer und Kruez.
Translation: Italian of complete trilogy by Alessandro Zabini as Le spade e l'impero, Nord 1997 (8842909971).
Awards: Honorable mention: 1996 Sidewise Award for best long-form alternate history.

Harrison, Harry, and John Holm. The Hammer and the Cross
Summary: A half-English, half-Danish bastard thrall falls in and out with Vikings who have mounted a massive invasion of England in 865 CE. He ends up king of a religously-tolerant northern England.
Series note: First volume of The Hammer and the Cross Trilogy.
Published: Legend 1993 (0099260514), 1994 (0099868202); Tor 1993 (0312854390BUY), 1994 (0812523482BUY).
— Included in Warriors of the Way, SFBC 1995 (1568651465).
Original in: English.
Translation: German as Der Hammer des Nordens, Heyne 2000 (345315648X).
Translation: Italian by Alessandro Zabini as La via degli dei, Nord 1996 (8842908894).
Translation: Polish by Piotr Szarota as Mlot i krzyz: Thrall, Amber 1995.

Harrison, Harry, and John Holm. One King's Way
Summary: King Shef takes the war against the Vikings to their homeland, with conflict and adventures throughout Scandinavia.
Series note: Second volume of The Hammer and the Cross Trilogy.
Published: Legend 1995 (009930306X), 1996 (0099303086); Tor 1995 (0312856911BUY), 1996 (0812536452BUY).
— Included in Warriors of the Way, SFBC 1995 (1568651465).
Original in: English.
Translation: German as Der Pfad des Königs, Heyne 2001 (3453156544).
Translation: Italian by Alessandro Zabini as Il trono di Asgard, Nord 1996 (8842909394).
Translation: Polish by Justyna Zandberg as Mlot i krzyz: Karl, Amber 1995.

Cover art
Harrison, Harry, and John Holm. King and Emperor. Tor 1996 (cover art by Gary Ruddell).

Harrison, Harry, and John Holm. King and Emperor
Summary: The conflict between Shef and the Holy Roman Empire continues into Spain as both sides seek the "Holy Graal", and then to the very gates of Rome.
Series note: Third volume of The Hammer and the Cross Trilogy.
Published: Tor 1996 (031285692XBUY), 1997 (0812536460BUY); Legend 1996 (0099303051), 1997 (0099303094); SFBC 1996.
Original in: English.
Translation: German as Hammer und Kreuz 3. König und Imperator, Heyne 2002 (Heyne).
Translation: Italian by Alessandro Zabini as Il re e l'impero, Nord 1996 (8842908665).
Translation: Polish by Marek Rudnik as Mlot i krzyz: Jarl, Amber 1995.

Harrison, Harry, and John Holm. Warriors of the Way
Series note: Omnibus of The Hammer and the Cross and One King's Way.
Published: SFBC 1995 (1568651465).