The Sidewise Awards 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 go all topsy-turvy and 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 and have included judges in the United States, United Kingdom, Canada and South Africa.
Two awards are normally presented each year, usually at WorldCon or at NASFiC. The Short-Form award is presented to a work under 60,000 words in length. The Long-Form award is presented to a work or works longer than 60,000 words, which may include a single novel or a multi-volume series. The judges have four times also recognized an individual with a Special Achievement Award in recognition for works published prior to the award's inception or for other contributions to the genre.