Horrible Histories is an educational entertainment franchise encompassing many media including books, magazines, audio books, stage shows, TV shows, and more.

In 2013, Lisa Edwards, UK publishing and commercial director of Scholastic Corporation, described Horrible Histories as one of the company's "crown jewels", and said it is at an "advanced stage of evolution". She added: "We have covered every possible era that has a commercial outcome...We're now in the era of the box set, annuals, newly presented editions and licensed products".

Horrible Histories began as a book series by author Terry Deary. The series began in 1993 with The Terrible Tudors and The Awful Egyptians, and the following titles continued the trend to describe British history through the context of the ruling dynasties, as well as explore significant worldwide cultures (often within the context of British history such as the Viking and Roman conquests on the British Isles). A series of specials and novelty books have been released, and the last book was announced to be released in 2013.

There is also a fiction-type of Horrible Histories books that were added to the series called Gory Stories. The first set of these books were published in July 2008:

Blackout in the Blitz is listed on Terry Deary's website as Bombs on Britain, but on Amazon.co.uk it is listed as Blackout in the Blitz, along with a cover.

Horrible Histories was adapted into an animated series consisting of 26 episodes and airing from 2000 to 2001. The premise revolves around kids Mo and Stitch's adventures through time and how they learned lessons that could be applied to their modern-day situations.

A live-action series, styled as a sketch show, began airing on CBBC in 2009. It won many awards over its 5 series run, including some British Comedy Awards – the first children's show to do so.

Horrible Histories with Stephen Fry was an edited version of the 2009 series hosted by Stephen Fry instead of Rattus Rattus, broadcast in 2011, and was aimed at an adult audience.