It is a previously taboo world of lust, lasciviousness, sexual candour and eroticism.

But now the hidden history of 500 years of Gaelic love, sex and "transgressive" verse is to be brought into the open with a major new compendium of the poetic "subculture".

An Leabhar Liath / The Light Blue Book: 500 years of Gaelic Love and Transgressive verse, to be published in January by Luath Press, features more than 60 poems and lyrics from some of the most candid examples of Gaelic love poetry, chosen by editors Peter Mackay and Iain S Macpherson in a dual-language anthology.

The volume covers candid literary ground from Sorley MacLean back to 15th century, and features ardent love poetry as well as cruder poems that take Gaelic poetry beyond a traditional landscape glens and islands.

Some of the poetry has not been translated into English before and the editors combed Gaelic books, publications and manuscripts, from the popular to the very obscure, covering five centuries of verse, including waulking (making tweed) songs, sheiling (hillside) songs, as well as anti-clerical and anti-courtly rhymes.

The editors say: "Most of the poems and songs can best be seen as bawdy or erotic: they depict sex (or, in lighter moods, love) with differing degrees of explicitness or rudeness.

"If one were to apply the British Board of Film Classification labels to the poems few would actually belong to the 18 category, and many would safely be PG."

There are poems that include frank depictions of male and female genitals, boastful accounts of the size of a man's penis, blood-drinking, the eating of sheep’s testicles, the torture and castration of Mussolini as well as the anonymous ‘Ailean Dubh à Lòchaidh’, in which a woman celebrates the survival of her beloved, even though he has stolen her cattle and burnt her oats and barley.

The first poem, from 1510, by Iseabal Ní Mheic Cailéin, Countess of Argyll, begins: 'Listen, everyone in the house,

to the tales that have been written/of the energetic c*cks/with which my heart is smitten.'

The editors note that "a few pieces here might be considered ‘obscene’; this, however, raises the question of what is meant by ‘obscene’ or, indeed, ‘bawdy’ or ‘erotic’."

Waulking or fulling of tweed, the book's introduction says, offered an exclusively female environment in which women could ‘bitch, giggle and lose their inhibitions."

Dr Mackay, of the University of St Andrews, said: "Certainly in the past, we can see that people were more frank about matters, and they were perfectly able to call a c*ck a c*ck.

"This is certainly the first book of its kind that we know of, it is trying to identify a tradition that not many people know about."

He said the "Balmoral-isation" of the public's view of the Highlands in the 19th century meant that verse of such a kind, also repressed for religious and social reasons, meant that people in poems "were only going to get naked to freeze and die, rather than anything else".

He said the translations, while sometimes impossible to translate directly, try to "register the right level of offence" in the text.

In his introduction, he writes that the greatest [Gaelic] poet of them all, Alexander MacDonald (Alasdair Mac Mhaighstir Alasdair, c1698–c1770) could be "avowedly, exuberantly, excessively rude, (porno)graphic and blue."

In 1829, he notes, the Rev Dr Mackintosh MacKay, once moderator of the general assembly of the Church of Scotland, wished MacDonald’s obscene work destroyed, "as its most deserved fate, we should like to see it burned by the hand of the common executioner".

He adds that there is a "long and healthy tradition – or counter-tradition or subculture – of bawdry, erotic or love poetry that stretches as far back as the age of Ossian.

"This anthology aims to give a glimpse into this tradition, in its breadth and depth, gems, treasures, warts and all."