This 24-square-mile outcrop, 80 miles from the British mainland and 30 miles from Normandy, still prohibits the purchase of petrol on the Sabbath. It also still has a statute of 1910 that outlaws abortion and sets down jail terms of three years to life for trangressors and doctors who assist them. It is pressure to change this law that has shattered the island's tranquillity.
The law has not been used in a prosecution since 1950. But as the local Board of Health prepares a submission on the matter for the States of Deliberation, the 55 elected representatives who draw up the island's laws, the battle between pro-life and pro-choice groups has started to suck in the big guns from the British mainland.
The pro-choice heavyweight Claire Rayner recently addressed a public meeting, larger than any held on the island since the war. The Society for the Protection of Unborn Children is training a group advised by Cynthia Kennedy, former leading light in the American Right to Life movement and a wealthy newcomer to Guernsey.
In her palatial home on the island, Cynthia Kennedy sits propped up by pillows, rigid in a neck brace after back surgery. She is in pain but her predicament brings a smirk to the lips of opponents. "She's a robot," warns one. "Her eyes don't blink and glaze over when she gets started. She is so sure she's right she'll concede nothing."
Soft-spoken, honey-blonde and looking younger than her 47 years, Mrs Kennedy rolls her eyes at the suggestion that she came to Guernsey as an international pro-life agent. As former executive member of Michigan Right to Life, she ran a counselling service for pregnant women right next door to Planned Parenthood, a family planning agency, but insists she came to Guernsey last summer because of her English-born husband's job.
Her religious beliefs are rooted in the Presbyterian faith of her forefathers - Dutch settlers - and, inevitably, in scripture. Enjoying pride of place on the sideboard is a beautifully bound copy of the Parables. Feminists, she says, have demeaned the role of mother and propagate the lie that abortion liberates women.
Mrs Kennedy was pregnant with her first child when the US Supreme Court legalised abortion in 1973. Since then she and her family have lived and breathed the issue, surrounded by pro-life literature and plastic models of foetuses at various stages of development. Mrs Kennedy educated her five children - aged 16-22 - at home. At university her eldest daughters "bravely" buck liberal trends and compose pro-life dissertations.
"Science proves we have a living human being from the moment of fertilisation," she insists. "The unborn child is the most defenceless of all human beings and deserves our protection and that of the law. To abort is always to kill a baby." A beatificsmile is offered rather than a steely glare, but it's clear nothing is up for negotiation.
Laura Kennedy, 16, listens intently. Tall, clean-cut and Mormon-straight, she is fulfilling parental expectations. She and a friend have just launched the youth wing of the Guernsey Right to Life group. "I'm just so proud of her," says her mother. "They have done it all without adult help."
It is, in fact, a counter-attack; two local schoolgirls recently grabbed headlines by gathering 300 signatures in support of abortion. But the pro-lifers' attempts to take the battle into the playground have so far failed, although they have donated foetal models to every school.
Mrs Kennedy's tactics are going down badly among her opponents. The latest complaints centre on "offensive" pamphlets, but these follow emotive advertisements in the local press, including one on Mother's Day. In letters to the Guernsey Evening Press, pro-lifers have compared opponents' meetings to Nuremberg rallies.
Graham Ingrouille, the paper's editor, says the pro-lifers got off to an early and insensitive start: "We had to ask people to tone down letters. They were talking about babies being slaughtered. We thought the point could be put over without upsetting people, including a lot of Guernsey women who have had abortions."
The late arrival of the debate in Guernsey, almost 30 years after Britain legalised abortion, is as surprising as the virulence of both the campaigns. With the exception of Northern Ireland, it now stands alone in the British Isles. Jersey, its bigger, richer sister, gave in to pressure to legalise abortion last year, although the law has not yet been ratified. The Isle of Man decriminalised abortion this summer.
According to Pippa McCathie, a mother of three and founder of the Guernsey Women's Group, the delay is due to a combination of male chauvinism, conservatism, apathy and affluence. She started GWG in 1993 after Guernsey refused to approve a UN convention on women's rights to which even Bangladesh, where women have few formal rights, is a signatory. "People are just too comfortable. There isn't even any equal opportunities legislation here."
Jenny Moore, 50, co-founder of the Guernsey Pro-Choice Group, agrees. "Women on Guernsey are not radical or politically aware and islanders find this entire subject distasteful. When you are living in a community of 60,000 you have to be brave to stand up on something like this."
In the face of a hard-hitting campaign by the other side, the island's pro-choicers have forged some unlikely alliances. Mrs Moore, former chief executive of Guernsey Chamber of Commerce, and Mrs McCathie, a rare out-and-proud Guernsey socialist, have not campaigned together before. Abortion, they claim, is also making first-time activists of women more used to the charity, coffee-morning or cocktail circuits than the dirty business of local politics. Here, pro-choicers are rich little old ladies who write pledging not only their own support but also that of their cleaners. What unites them is deep dislike and suspicion of Cynthia Kennedy.
To Alison, 37, Mrs Kennedy is a rich outsider whose wealth cushions her from hard realities. Three years ago Alison, a divorcee and mother of two young children, became pregnant by her boyfriend after contraception failed. Her relationship was not stable and she could not cope with sole responsibility for another child. "I was already working full-time to support the two children who were much wanted," she says. "It's fine if you have plenty of money but many of us have a struggle raising children.
"I had to go to Brighton for the abortion. There were three other girls from Jersey and Guernsey there at the same time. There will always be accidental pregnancies. What are women like me expected to do? Not have sex in case contraception fails? How dare Cynthia Kennedy tell me what to do. We should dump all those unwanted children on her lawn."
Ann, 28, is similarly incensed. She was divorced and raising a four-year- old daughter without maintenance when contraception failed. Her boyfriend wanted the child but she felt the relationship was too weak.
"I was already just keeping my head above water. My house, my job, everything I'd achieved for my daughter was at risk. It wasn't an easy decision but I still feel it was the right one."
But Guernsey's laws made her feel like a criminal. "My doctor could only offer some ancient photocopies of British Pregnancy Advisory Service leaflets. I borrowed some money and went away for a couple of days. But what chance do younger, poorer, less informed girls have?"
Guernsey's Anglican church leaders agree that the law must change and have dared to suggest that abortion is not wrong in all circumstances. This has infuriated other churches, particularly the evangelicals.
Pippa McCathie believes that the matter will be determined by 10 to 15 undecided representatives; the remaining members are thought to be evenly divided. With voting unlikely to take place before early next year, both sides think there is everything still to fight for.