A passionate defence of gay rights written more than two centuries before homosexuality became legal has been discovered.

Homosexuality was illegal in Britain until 1967, but a University of Manchester academic has unearthed a scroll written by a pioneering gay activist that dates back to the 18th century.

The handwritten parchment indicting the printer of Thomas Cannon’s 1749 book, Ancient And Modern Pederasty Investigated And Exemplified, was found at the National Archive in Kew. Dr Hal Gladfelder stumbled across the dusty scroll, which contains extracts from the book, while doing research.

The book, which was suppressed immediately after its publication, appears to be an anthology of stories and philosophical texts in defence of male homosexuality.

The printer had to flee to continental Europe to avoid punishment and no copies of the book itself survive.

One story deals with cross-dressing and others are translations of Greek and Latin homoerotic texts.

It also includes the passage: “Unnatural desire is a contradiction in terms; downright nonsense. Desire is an amatory impulse of the inmost human parts.”

Dr Gladfelder said: “This must be the first substantial treatment of homosexuality ever in English. “The only other discussions of homosexuality were contained in violently moralistic and homophobic attacks or in trial reports for the crime of sodomy up to and beyond 1750.” Sodomy was a capital offence punishable by death until 1861.

Dr Gladfelder added: “I think what happened to Cannon paved the way for 200 years of homophobic repression.”

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