The man standing in the dock of the Supreme Court of Van Diemens Land did not look like someone who was, as the Hobart Town Gazette put it on June 25, 1824, "laden with the weight of human blood, and believed to have banqueted on human flesh". In fact, he looked perfectly normal. He was 1.6 metres tall, slightly under medium height for the early 19th century, and his frame was wiry and strong. He was 34, but looked older.

There was nothing to distinguish the Irish-born Alexander Pearce from the procession of convicts who traipsed through the Hobart Town courts. Except for one thing - he was the first self-confessed cannibal to have appeared there.

Twenty months earlier, Pearce and seven other convicts had escaped from the prison settlement of Sarah Island, in Macquarie Harbour on the west coast of Tasmania, the most remote penal hellhole in the British Empire. In the jargon of the time, this was a place of secondary punishment, where recalcitrant convicts were sent when they repeatedly fell foul of the law while serving their original sentences. Pearce was the sole survivor of their nine-week escape through some of the world's most difficult wilderness terrain.

During their journey, five of his companions had been killed and eaten by their fellows. Two others died from exhaustion. Because cannibalism was unheard of among Europeans, Pearce's trial for murder created a sensation in Hobart Town, London, and even the United States.

Although Pearce was hanged in 1824, I keep meeting people who have heard of him. Perhaps it is the song about his exploits, A Tale They Won't Believe, by the group Weddings, Parties, Anything that has popularised him. He seems to be entering into popular consciousness, somewhat like Ned Kelly.

Pearce originally had been sentenced at the County Armagh Lent assizes of 1819 to transportation for seven years. His crime was stealing six pairs of shoes, probably not his first offence. Only a professional thief would steal six pairs.

Pearce quickly distinguished himself as a troublesome malcontent. Between his arrival in Tasmania in February, 1821, and early August, 1822, when he was sent to Macquarie Harbour, he had absconded twice, received four floggings, one of 50 lashes for embezzling two turkeys and three ducks, one of 25 and another of 50 for being drunk and disorderly, and another 50 and six months working in chains for stealing a wheelbarrow.

In March, 1822, Pearce absconded again. After three months he was recaptured. By now the none-too-merciful magistrates of Hobart Town had had enough of him and he was sent to Macquarie Harbour for the remainder of his original sentence. He was there about six weeks when he bolted into the bush with seven others, beginning the extraordinary journey that has become famous in the history of penal Australia.

The whole area of the west coast then was separated from the settled districts in the centre of Tasmania by difficult and unexplored terrain.

Both guards and prisoners found Macquarie Harbour dreary and the weather appalling. The prisoners' main work was cutting and transporting the Huon pine logs and other fine timber, which grew abundantly in the area and were excellent for boat-building.

Today the area around Macquarie Harbour is valued precisely because of its isolation and is protected as one of the most spectacular wildernesses on Earth. This is a land of cool, temperate rainforests, the most extensive remnant of the extraordinary vegetation of the great southern supercontinent Gondwana.

These forests are of myrtle beech, celery-top and King Billy pine, and the most ancient of all conifers, Huon pine, which lives for up to 3000 years, and is found only in Tasmania.

On September 20, 1822, the convicts Alexander Pearce, Alexander Dalton, Thomas Bodenham, William Kennerly, Matthew Travers, Edward Brown, Robert Greenhill and John Mather were cutting Huon pine logs on the eastern side of Macquarie Harbour. Fed up with the rigid discipline, they planned to escape.

They intended to commandeer a whaleboat, sail north out of Macquarie Harbour, heading to freedom on a Pacific island, or even China. They easily overpowered their overseer, but they bungled the getaway. So they plunged impulsively into the rainforests and mountains surrounding the harbour. They headed east but they were utterly ill-equipped for what lay ahead on their 225-kilometre journey.

Nowadays this region is regarded as some of the toughest country in the world, visited only by experienced bushwalkers with good equipment. Eight days into their hellish journey and by now starving, the men realised that their only hope for survival was cannibalism. Almost impulsively, they killed and ate Alexander Dalton because, Pearce says, he had volunteered to be a flogger and such men were hated.

Next day, fearing that they might be the next victims, Brown and Kennerly decided to return to Sarah Island. Anything would be better than being killed and eaten by their fellows in the wilderness. They made it back to the coast of Macquarie Harbour, but died from exhaustion soon after.

The other five men continued, led by Greenhill, who had been a sailor. It was his navigational skills, using the sun and the stars, that enabled the party to travel for 42 days almost due-east towards the settled areas. It was an extraordinary feat.

As the journey continued, one by one, the weakest man was killed with an axe and butchered to provide food for the others. After five weeks of endless walking, only three men were left: Greenhill, Pearce and Travers. Most of the killing had been done by Greenhill, but Pearce and Travers had also participated. At first they cooked the flesh and innards, but eventually they just ate them raw. By this stage they had reached less rugged country, but with no knowledge of the bush they were unable to live off it.

Driven by extreme hunger, Greenhill finally faced the prospect of having to kill his injured friend Travers, who had been bitten on the foot by a venomous tiger snake. With Travers' foot now gangrenous, Greenhill and Pearce half-dragged and carried their injured companion for five days until Travers begged them to kill him. The only weapon left was the axe. They killed him in his sleep, and ate his flesh.

But the problem with human flesh is that, while rich in protein, it never really satisfies hunger because of the lack of carbohydrates, which provide energy. That is why the men had to kill so regularly. No matter how much they ate of their companions, it was not enough for the energy needed on their stamina-sapping journey.

Pearce and Greenhill struggled on for eight days, playing cat and mouse with each other, desperate to stay awake, fearing that the other would attack him if he closed his eyes and nodded off. It was Pearce who kept awake long enough to grab the axe and kill the sleeping Greenhill with a blow to the head.

The Irishman eventually made it to the settled districts, was befriended by a convict shepherd, and lived rough for several months, robbing farms and stealing sheep, before he was recaptured.

Incredibly, when Pearce gave an account to the authorities of the nightmare journey and the cannibalism involved, the examining magistrate and local parson, the Reverend Robert Knopwood, did not believe him, thinking that Pearce concocted the story to cover for his mates who were believed to be still at large. Pearce was returned in chains to Sarah Island, where his fellow convicts treated him as a hero.

Several months later he bolted again from a work party, this time heading north along the east coast of Macquarie Harbour with a young man named Thomas Cox, who had pestered Pearce to accompany him on an escape attempt.

When Pearce surrendered 11 days later near the mouth of the King River, just south of present-day Strahan, he had human flesh in his pocket.

Why he felt the need for cannibalism again is a mystery, since the guards found that he had other food with him. Pearce, who was clearly a psychopath, said that human flesh was by far preferable to ordinary food. Obviously he had acquired a taste for it, and for killing.

Pearce later admitted that he had murdered Cox in a rage, because he suddenly realised that the young man could not swim, and was going to be a continuing hindrance to him.

At Pearce's trial, witnesses said he had given himself up because he had no hope of ultimately escaping, and that he was horror-struck at his own inhuman conduct. This sounds like a sanitised account, but we know that he showed signs of repentance at the time of his execution.

It was very cold - there was heavy snow on Mount Wellington - in the court room on that winter day, June 20, 1824, when the cannibal stood trial for murder. The chief justice, John Lewes Pedder, presided at the trial for the murder of Thomas Cox. Pedder was a scrupulous judge, but he often hectored the condemned from the bench, telling them that they should not complain about harshness when penalties were well known to everyone.

The prosecutor was the attorney-general, Joseph Tice Gellibrand. Ironically, Gellibrand was to become lost in the bush near Melbourne in 1837, and was almost certainly killed by Aborigines.

Pearce had no defence counsel and there is no record that he said anything on his own behalf. The trial was brief and the inevitable verdict was handed down. The chief justice pronounced the death sentence and ordered that the body be delivered to the surgeons for dissection.

Thirty days later, after receiving the sacraments from the Catholic chaplain, Father Philip Conolly, Pearce was hanged in the yard of the Hobart Town jail at 9am on July 19, 1824.

Handing over the body for dissection was an uncommon addendum to the death sentence, but in the logic of 19th-century criminal justice it made eminent sense: the corpse of the cannibal was to be cannibalised for science. Thus ended one of the great Gothic horror stories of Australia's rich convict history.

Paul Collins is the author of Hells Gates: The Terrible Journey of Alexander Pearce, Van Diemen's Land Cannibal

Narrative of the escape of eight convicts from Macquarie Harbour c.1824
manuscript; 26.4 x 22.0cm
Bequeathed by Sir William Dixson, 1952
Dixson Library, State Library of New South Wales

Alexander Pearce, pencil drawing by Thomas Bock.