The Sidewise Award for Alternate History were established in 1995 to recognize the best alternate history stories and novels of the year.
The awards take their name from the 1934 short story "Sidewise in Time" by Murray Leinster, in which a strange storm causes portions of Earth to swap places with their analogs from other timelines.
The awards were created by Steven H Silver, Evelyn C. Leeper, and Robert B. Schmunk. Over the years, the number of judges has fluctuated between three and eight, including judges in the UK and South Africa.
Each year, two awards are presented, usually at Worldcon. The Short-Form award is presented to a work under 60,000 words in length. The Long-Form award may be presented to a work longer than 60,000 words, including both novels or complete series. At their discretion, the judges may also elect to recognize an individual or work with a Special Achievement Award in recognition of works that were published prior to the award's inception.
- 2007 Michael Chabon, The Yiddish Policemen's Union
- 2006 Charles Stross, The Family Trade, The Hidden Family, and The Clan Corporate
- 2005 Ian R. MacLeod, The Summer Isles
- 2004 Philip Roth, The Plot Against America
- 2003 Murray Davies, Collaborator
- 2002 (tie) Martin J. Gidron, The Severed Wing & Harry Turtledove, Ruled Britannia
- 2001 J. N. Stroyar, The Children's War
- 2000 Mary Gentle, Ash: A Secret History
- 1999 Brendan DuBois, Resurrection Day
- 1998 Stephen Fry, Making History
- 1997 Harry Turtledove, How Few Remain
- 1996 Stephen Baxter, Voyage
- 1995 Paul J. McAuley, Pasquale's Angel
- 2007 (tie) Michael Flynn, "Quaestiones Super Caelo Et Mundo" & Kristine Kathryn Rusch, "Recovering Apollo 8"
- 2006 Gardner Dozois, "Counterfactual"
- 2005 Lois Tilton, "Pericles the Tyrant"
- 2004 Warren Ellis, The Ministry of Space
- 2003 Chris Roberson, "O One"
- 2002 William Sanders, "Empire"
- 2001 Ken MacLeod, "The Human Front"
- 2000 Ted Chiang, "Seventy-two Letters"
- 1999 Alain Bergeron, "The Eighth Register" (translated by Howard Scott)
- 1998 Ian R. MacLeod, "The Summer Isles"
- 1997 William Sanders, "The Undiscovered"
- 1996 Walter Jon Williams, "Foreign Devils" (in War of the Worlds: Global Dispatches)
- 1995 Stephen Baxter, "Brigantia's Angels"
- 1999 Randall Garrett: The Lord Darcy Series
- 1997 Robert N. Sobel: For Want of a Nail
- 1995 L. Sprague de Camp, lifetime achievement