Horrible Histories have been turned into a motion picture, three TV series, videogames, and board games among others. Groovy Greeks was adapted into a play in 2015 by The Birmingham Stage Company.

Groovy Greeks has been translated in several languages, including:

Dutch: Die gave Grieken, Waanzinnig om te weten, Alkmaar: Kluitman, 1998.

Italian: I Ganzi Greci, Brutte Storie, Milano: Salani, 1997.

Polish: Ci rewelacyjni Grecy, Strrraszna historia, Warsaw: Wydawnictwo Egmont Polska, 1998.

Portuguese: Os Gregos Baris, Os Horríveis, 2001.

Spanish: Esos Supergeniales Griegos, Esa Horrible Historia, Barcelona: Molino, 1996.

The play Horrible Histories: Groovy Greeks expands on some of the themes of the book.

A humorous overview of the mythology and history of Ancient Greece. After an introduction to Greek "gruesome gods" and "petrifying plays and electrifying epics", Deary zooms in on the "savage Spartans" and the "odd Athenians". He then summarises the Persian and Peloponnesian Wars, before giving an entertaining account of the life and deeds of "Alexander the Great-er". The following chapters describe how Ancient Greeks thought, lived, and died, with sections about their food, their games, and the Olympics. The book concludes with the arrival of the Romans and the story of Archimedes’ death, "a good example of what the world lost when the rotten Romans took over from the groovy Greeks…" (p. 127).

Groovy Greeks is Horrible Histories at their best: funny, engrossing, and (mostly) accurate. Deary knows how to skilfully balance entertainment and dissemination, squeezing more than a thousand years of Greek history into 128 pages of quizzes, jokes, and fun facts. His cheeky humour brightens up the retellings of myths (for example, we get to read Clytemnestra’s diary at pp. 26–34, inspired by Aeschylus’ Agamemnon) as well as less-known historical episodes (e.g. Charidemus’ capture of Troy at pp. 18–23, based on a passage in Aeneas Tacticus’ treatise on sieges [24.3–14]).

Deary’s notorious intolerance of teachers and their presumption of "know[ing] everything" (e.g. Crace 2003) emerges in a series of caustic vignettes, where teachers are tested (pp. 86–8), ridiculed (pp. 44, 92), and even throw spears and arrows at (p. 84). Historians are presented in a more positive light (pp. 35–6, 61–3), although Deary has recently defined them "nearly as seedy and devious as politicians" (Anonymous 2010; see also De Groot 2009, 39–42). In line with the anti-establishment views of the author (see Henley 2012), religion is mocked as "just a con trick created to make money for the priests" (p. 37).

While the historical narrative is generally accurate, some of the anecdotes presented as facts are well-established faux myths (e.g. Archimedes’ burning mirrors at p. 127, which would have been utterly ineffective; see Mills & Clift 1992 and Jaeger 2010, 159–160, n. 19). Other inaccuracies are more surprising and rather problematic. In the timeline, Deary states that in 730 BC the Greeks "produce the first works of written poetry in the world" (p. 7), erasing about 1400 years of Eastern literary tradition (the Epic of Gilgamesh dates to c. 2100 BC). The same goes for the western-centric claim that the Greeks "invented" drama (p. 24).

Despite these issues, the volume, aimed at children and young teenagers, offers an engaging, irreverent alternative to traditional history books. Because of their popularity, several school libraries own at least some of the Horrible Histories titles and teachers use them profusely, to Deary’s dismay: "[t]hey are used by teachers to enliven their boring history lessons. Do they realise how subversive Horrible Histories are? Do they realise they’re undermining their own authority? If they did, they wouldn’t use them" (Preston 2013). However, it is precisely this subversiveness, combined with silly jokes and a stimulating interplay of visual and verbal elements (Kostuli 2005, 131), that make Groovy Greeks (like the other volumes in the series) such an outstanding teaching material. During his own experience as a teacher, Deary used to tell stories to the children before starting his classes, discovering the impact that narrative and storytelling can have on learning (Preston 2013). This intuition is brilliantly developed in his books, where individuals become the focus of the narrative and the past a powerful tool to understand the present: "All the time I want the reader to look at the people, the individuals that make up history. History in never boring when you look at it on the individual level. In Horrible Histories I’m asking, ‘Why do people do what they do?’ And, ultimately, ‘Why do I behave the way I do?’" (Deary, quoted in Carter 2001, 170).

Anonymous, “Historians are seedy and horrible, says Terry Deary, children’s author”, The Times (May 31, 2010), available at thetimes.co.uk (accessed: August 15, 2019).

Carter, James, Creating Writers: A Creative Writing Manual for Schools, Abingdon-on-Thames, UK: Routledge, 2002.

Crace, John, “Writing History”, The Guardian (August 12, 2003), available at theguardian.com (accessed: August 15, 2019).

De Groot, Jerome, Consuming History: Historians and Heritage in Contemporary Popular Culture, Abingdon-on-Thames, UK: Routledge, 2009.

Henley, Jon, “Terry Deary: The man behind the Horrible Histories Books”, The Guardian (July 4, 2012), available at theguardian.com (accessed: August 15, 2019).

Jaeger, Mary, Archimedes and the Roman Imagination, Ann Arbor, MI: University of Michigan Press, 2010.

Kostuli, Triantafillia, Writing in Context(s): Textual Practices and Learning Processes in Sociocultural Settings, Berlin: Springer Science+Business Media, 2005.

McKay, Sinclair, “Sinclair McKay meets Terry Deary, the creator of the Horrible Histories”, The Telegraph (September 1, 2009), available at telegraph.co.uk (accessed: August 15, 2019).

Mills, Allan A. and Clift, Robert, “Reflections of the ‘Burning mirrors of Archimedes’. With a consideration of the geometry and intensity of sunlight reflected from plane mirrors”, European Journal of Physics 13, 6 (1992): 268–279.

Preston, Richard, “Horrible Histories: 20 years of entertaining children”, The Telegraph (February 21, 2013), available at telegraph.co.uk (accessed: August 15, 2019).

Genre: ‘A fact book with jokes’, as defined by Deary himself (McKay 2009).