David Day was born and raised in Victoria, British Columbia. He is a poet and author who has published over 50 books of poetry, ecology, history, fantasy, mythology and fiction. David Day's books - for both adults and children - have sold over 3 million copies worldwide and were translated into twenty languages.

​After high school, Day divided the next decade between work in logging camps and study at universities. His first book of poems, The Cowichan (based on his timber camp journals) was published in 1975, and he graduated from the Department of Creative Writing at the University of Victoria the following year.

He was writer in residence at the Aegean School of Fine Arts in Paros, Greece, and worked for the Canadian Publishers McClelland Stewart in Toronto. He has subsequently travelled extensively, and lived in England, Greece, Spain and his native Canada. He currently lives in Toronto, Canada.

In 1978, he published A Tolkien Bestiary, the first of his dozen best selling books on the works of J R R Tolkien. In 1981, his Doomsday Book of Animals - with a forward by HRH the Duke of Edinburgh - was a 'Book of the Year' selection for Time Magazine, New Scientist, Los Angeles Times and The Observer. And in 1984, Day wrote Castles, the first of five books in collaboration with the Academy Award winning artist, Alan Lee.

In 1986, his children's novel, The Emperor's Panda was nominated for the Governor General's Award and the National Library Award, and was adapted for stage by the Toronto Young People's Theatre. He has subsequently published six illustrated books of children's stories and three illustrated books of children's poems. He has published a further six books of poetry that have been prizewinners in CBC and National Magazine Awards and have been praised by Canadian poets Al Purdy, Earle Birney, Margaret Atwood and the British poet laureate, Ted Hughes.

Through the 1980's and 1990's, Day published The Eco-Wars and The Whale Wars along with three other books on environmental activism. He was also an environmental columnist for Britain's Daily Mail, Evening Standard, Guardian, Sunday Times and Punch magazine. And after the 1996 publication of his Quest For King Arthur, Day was commissioned by the Birmingham Royal Ballet as dramaturge for the epic two-part ballet, Arthur I and Arthur II (2000).

David Day has also written for theatre and television. He scripted the 100-part Lost Animals of the Twentieth Century TV series (narrated by Greta Scacchi). The series was commissioned by the Discovery Channel in US, Channel 4 in UK and NHK in Japan, and later translated into 18 languages. His book The Whale Wars was the basis of the ITV documentary of the same name.He has also worked as creative adviser for Toronto's Hall Train Studios' multi-media museum exhibitions. And in 2014, he accompanies the artist John Howe in the French-German ARTE TV network documentary 'Looking For the Hobbit: Part 5. Lost Gold of the Rhine'.

​In 2015, Day published a major study of Lewis Carroll, entitled 'Alice's Adventures in Wonderland Decoded'. That same year saw the publication of A Dictionary of Tolkien and An Atlas of Tolkien, the first two of a set of six books in his Tolkien Reference Library over the following four years.

In 2019, the leather-bound An Encyclopedia of Tolkien: the History and Mythology that Inspired Tolkien's World (UK title: A Dictionary of Sources of Tolkien) and the large format The Illustrated World of Tolkien were published. While the year 2020, saw the publication of a special edition of his Tolkien Illustrated Guides Boxed Set (of 6) in the Word Cloud Classics series.

A ten minute video of the secrets of Alice's Adventures in Wonderland Decoded is available on http://www.daviddaybooks.com/media.html

Ten short documentaries from the Discovery Channel TV series 'Lost Animals of the Twentieth Century' may be viewed on www.youtube.lostanimals-daviddaybooks