Cover art
Turtledove, Harry. Agent of Byzantium. Worldwide 1988.

Turtledove, Harry. Agent of Byzantium
Divergence: 610 CE
What if: Mohammed became a Christian, and the lack of Islamic pressure meant Byzantium never fell but faced a technologically sophisticated Persia.
Series note: Series of short stories, all of which except for "Departures" are collected in Agent of Byzantium. "Departures" may be considered a prequel to the series proper.

Turtledove, Harry. "Departures"
Divergence: 610 CE
Summary: Christian monks, including a powerful hymn writer named Mouamet, flee a Sinai monastery for Constantinople as Persian forces approach.
Series note: Prequel to the Agent of Byzantium stories, providing detail on the what-if basis.
Published: In Isaac Asimov's Science Fiction Magazine, January 1989; What Might Have Been? Volume 2: Alternate Heroes (eds. Gregory Benford and Martin H. Greenberg), q.v.; and Departures, q.v.
Original in: English.
Translation: Italian by Roberto Di Meglio as "Partenze", in Isaac Asimov Science Fiction Magazine 2, Telemaco 1993.

Cover art
Turtledove, Harry. Agent of Byzantium. Translated to the Italian as L'agente di Bisanzio. Nord 1996.

Turtledove, Harry. Agent of Byzantium
Divergence: 610 CE
Comments: Collection of previously published stories. In internal chronological order, they are "The Eye of Argos", "Strange Eruptions", "Pillar of Cloud, Pillar of Fire", "Unholy Trinity", "Archetypes", "Images", and "Superwine", Pre-1990 eds. do not contain "Pillar of Cloud, Pillar of Fire". The story titles, however, are not used in the collection itself but are instead replaced with "chapter" headings identifying the years in which they occur.
Published: Congdon & Weed/Contemporary 1987 (0865531838); SFBC 1987; New English Library 1988 (0450421724); Worldwide 1988 (0373303017BUY); exp. Baen 1994 (0671875930BUY).
Original in: English.
Translation: Italian by Viviana Viviani as L'impero dei misteri, Peruzzo 1989. V.t., L'agente di Bisanzio, exp Nord 1996 (8842909106), Peruzzo 1998.
Translation: Portuguese by Eurico Fonseca as O Agente de Bizâncio, Livros do Brasil 1990.
Translation: Spanish as Agente de Bizancio, Ómicron 2008.

Turtledove, Harry. "The Eyes of Argos" [vt "Etos Kosmou 6814"]
Divergence: 610 CE
Summary: In the 14th century, Byzantine agent Basil Argyros discovers that the telescope has been invented in the steppes north of the Danube.
Published: In Amazing Stories, January 1986; Agent of Byzantium, q.v.; and There Will Be War 4: Guns of Darkness (eds. Jerry Pournelle and John F. Carr), Tor 1987.

Turtledove, Harry. "Strange Eruptions" [vt "Etos Kosmou 6816"]
Divergence: 610 CE
Summary: Argyros finds a cure for smallpox.
Published: In Isaac Asimov's Science Fiction Magazine, August 1986 and Agent of Byzantium, q.v.

Turtledove, Harry. "Pillar of Cloud, Pillar of Fire" [vt "Etos Kosmou 6818"]
Divergence: 610 CE
Summary: Argyros is sent to investigate the delay in the building of the new Alexandria lighthouse and discovers a labor strike.
Published: In Isaac Asimov's Science Fiction Magazine 15 December 1989; Agent of Byzantium, q.v.; and Departures, q.v.

Turtledove, Harry. "Unholy Trinity" [vt "Etos Kosmou 6824"]
Divergence: 610 CE
Summary: Argyros discovers the invention of gunpowder.
Published: In Amazing Stories, July 1985 and Agent of Byzantium, q.v.

Turtledove, Harry. "Archetypes" [vt "Etos Kosmou 6825"]
Divergence: 610 CE
Summary: Argyros investigates numerous identical seditious handbills appearing near the Persian frontier.
Published: In Amazing Stories, November 1985; Agent of Byzantium, q.v.; and The Way It Wasn't: Great Science Fiction Stories of Alternate History (ed. Martin H. Greenberg), q.v.

Turtledove, Harry. "Images" [vt "Etos Kosmou 6826"]
Divergence: 610 CE
Summary: Argyros is embroiled in an argument about religious icons.
Published: In Isaac Asimov's Science Fiction Magazine, March 1987 and Agent of Byzantium, q.v.

Turtledove, Harry. "Superwine" [vt "Etos Kosmou 6829"]
Divergence: 610 CE
Summary: Argyros is also there for the invention of brandy.
Published: In Isaac Asimov's Science Fiction Magazine, April 1987; Agent of Byzantium, q.v.; and High Adventure: Tales of Exploration, Escape, and Intrigue (eds. Cynthia Manson and Charles Ardai), Barnes & Noble 1993 (1566192811BUY).