IT WAS half-past three in the morning when the police commissioner heard the crowd approaching. He got out of bed. His wife sent a child out to get help but it was too late. They kicked his door in. He jumped from an upstairs window towards the safety of a neighbouring house but missed his footing and fell. A gang of 200 men in the street below seized him and beat him with clubs while his wife hid inside, cowering in an oven.

Joaquim Firmino de Araújo Cunha was murdered on February 11th 1888 in Rio do Peixe, a town that, in a sense, no longer exists. The crime was too big for a small place: Rio do Peixe changed its name to Itapira to start anew. It sits in an agricultural area that is hot, wet and green, where fertile soil permits the cultivation of sugarcane, oranges, coffee, and the raising of cattle. Itapira is in São Paulo state but far from the southern hemisphere’s biggest city, the municipal equivalent of a Hollywood star’s distant cousin. Itapira is known, if at all, for its three hospitals for the mentally ill, a large number for a population of 70,000 and the source of its nickname: the cidade dos loucos, or city of the crazies.

The murder was unusual, though not so much on account of its violence as because of the people involved. A police delegado, a position held by a citizen of some standing who volunteered for the job, made for an unusual victim. The suspect was even more exotic. According to newspaper reports at the time, the man responsible was an American doctor called James Warne. How did Dr Warne come to be in this small town, in the middle of the night, with his hands around the throat of the police commissioner?

Warne’s journey to the crime scene began in the south-west of England, took him across the battlefields of America’s civil war and from there on to Rio de Janeiro. His story shows how America and Brazil were once bound together by slavery, and how the end of the peculiar institution in one country helped, in a roundabout way, end it in another.

Warne was an unusually cultivated murderer. He was born in “Somersetshire” according to his war records. Britain’s 1841 census has a James Warne, pupil, living in Somerset, which would put him in his late 50s on the night of the murder. He came from a moderately wealthy family. When his father, William Warne, emigrated to America with the family he had enough capital to participate in a tin-mining company in Tennessee in the 1850s. There was money to send his son, James H. Warne, to study in Philadelphia and Nashville, where he qualified as a doctor of medicine in 1857. The topic of his thesis is listed as “Oxygen Gas”.

The gold rush following the 1848 finds in California took most prospectors west. The Warnes, however, moved east in search of instant wealth. North Carolina had once been home to America’s richest mines. William Warne heard the tale of a man who had been out chopping saplings in Clay County, North Carolina, only for his axe to bounce off something solid, yellow and shiny. Gold! In 1859 the Warnes paid $7,000 for the mine, which sounds a lot like one of Mark Twain’s holes with a liar standing next to it. It seems unlikely that they got the money back.

America, which had created fortunes for people who had started out with far less, had disappointed the Warnes. And now the country was turning in on itself. From North Carolina it felt like the North was asserting unwarranted dominion over the South; was set on destroying a civilisation of hooped skirts and plantations worked by negroes that it neither cared for nor understood. Warne volunteered to go to war. The recently qualified doctor joined the 39th North Carolina regiment in April 1862 as a surgeon.

The Warnes’ losing streak continued on the battlefield

The Warnes’ losing streak continued on the battlefield. In October 1862 Warne’s regiment took part in a battle at Perryville in Kentucky. The surgeon’s sleeves must have been soaked in blood: 530 of his side were killed and 2,600 wounded. The Union troops took more casualties but won the battle, keeping control of Kentucky for the rest of the war. From there the 39th North Carolina regiment moved on to Murfreesboro in Tennessee, where it took part in the battle of Stones river. The surgeon would have been busy here too. A greater proportion of the 75,000 men fighting at Murfreesboro was killed or wounded than in any other battle of the civil war, bodies punctured and broken by artillery fire. It ended in defeat for Warne and his fellow Confederates. The fighting continued for another two years but Warne’s part in it was over. A year after he joined the regiment he was dismissed, an unusual thing to happen to a surgeon and something that must have carried considerable shame with it.

Defeat brought sharp pain, even to those southerners who had not faced the bullets. “My heart is filled with an intensity of hatred toward the authors of our misery that I cannot mollify,” wrote one woman in a letter sent from Savannah in 1865. “There is no happiness within or without. I cannot reconcile myself to this wretched servitude.” Rather than stay put and face being reconstructed, some of the defeated moved farther west. For others, Oklahoma was not far enough from Washington, DC. They looked farther south, to Brazil: a country that, before the purchase of Alaska at the end of the 1860s, was as big as America, and which was one of the few remaining places where a white man could own slaves as was God’s intention, revealed in the book of Genesis.

Though America had banned the import of African slaves from 1808, its ships continued to sail to Africa to take part in the trade. American firms such as Maxwell, Wright and Co helped finance Brazilian slavery. American-registered boats set out from east coast ports, often disguised as whalers to avoid attracting attention, and sailed to southern Africa to load up on slaves before selling their cargo in Rio de Janeiro. Sometimes the slave ships would sail east flying a Brazilian flag and then switch on the return route to the stars and stripes, in the hope of discouraging British anti-slaving squadrons, nervous about boarding American ships, from intercepting them. It was worth the risk: a slave could be bought on the Congo river for $25 in the 1850s and sold for $500 or more. Brazil’s appetite for slaves meant that the transatlantic slave trade did not peak until the middle of the 19th century, three decades after both Britain and America had supposedly forbidden it. Before it was over, more than ten times as many Africans would be taken to Brazil as slaves as to America.

The demand for slaves made Brazil the obvious solution to the problem that had delayed abolition in America: how to compensate southern plantation owners for the loss of their property. The planters would sell their slaves to Brazilian farmers. “Just as the Mississippi valley has been the escape valve for the slaves of the northern, now free, states,” thought Matthew Maury, a prominent Virginian, “so will the Amazon be to that of the Mississippi.” He organised an expedition to explore the Amazon and test the feasibility of the idea. This thought was not as eccentric as it seems. Lincoln favoured various schemes for the mass deportation of freed African-Americans to the Caribbean (he was particularly keen on sending them to Belize and Guyana).

After the civil war Brazil took on a powerful appeal to southerners in search of new opportunities who also wished for life to continue much as it had before. In 1866 the Reverend Ballard Dunn published “Brazil, a Home for Southerners”. Dunn, an episcopal preacher from New Orleans, had founded a small colony in São Paulo state and named it Lizzieland, after his late wife. A year later James McFadden Gaston, a doctor from South Carolina, published “Hunting a Home in Brazil”, a cross between a travelogue and an estate agent’s prospectus.

Around 10,000 southerners moved to Brazil in the 1860s and 1870s, according to Gerald Horne of the University of Houston, one of the largest emigrations in American history. Among them, according to passenger records from the ships that docked in Rio de Janeiro, was a James H. Warne. He arrived in January 1866 on board a ship called the Santa Maria, eight months after the end of the war and three years since he had been dismissed from his regiment.

The new immigrants were initially welcome. The wealthier Americans bought plantations that came with black slaves. Others secured cheap land with easy financing. Warne appears twice more in port records during the following year, shuttling between Rio de Janeiro and Santos, the main port in São Paulo state, where he eventually settled. The confederados, as they later became known, founded a handful of settlements, most of which failed owing to the combination of difficult soil, poor roads and biting ants that had disheartened many colonists before them. But one, around the town of Americana in São Paulo, flourished. The headstones on its cemetery contain names like Carlton and Cobb, Smith and Steagall, some decorated with the star-crossed Confederate flag.

Brazil was very different from America. In the United States, only Mississippi and South Carolina had ever had majority black populations. In Brazil whites were a minority. Its largely white elite was wondering whether it could keep such a large number of Africans in order. At the same time, urban Brazil was becoming a little ashamed of the country’s reputation as the world’s slave capital. Around 20,000 Americans passed through Rio de Janeiro on their way to California’s goldfields from 1849 onwards, the route around Cape Horn being less arduous than the overland trek. Some had never seen slavery at home and wrote about it in letters and diaries. “The harbor is constantly covered with the bodies of blacks known to have thrown themselves in to escape,” wrote one. “I have seen them myself left…by the tide on the sand.”

By the time the confederados arrived in Brazil it was illegal to import slaves, though the practice of slavery continued. They did not know it, but the southerners were in some sense part of Brazil’s plan to wean itself off a dependency on an economic model that relied on kidnapping people in Mozambique, transporting them across the Atlantic and forcing them to work for nothing.

Warne’s fortunes in Brazil seem to have followed their previous trajectory. Around the time of his arrival his name appears in a newspaper in connection with an ambitious plan for an American colony in São Paulo state that was being frustrated by officials. In March 1866 he placed an advert in the Diario de S. Pãulo seeking funds. Two years later his name appears in the same paper, alongside other subscribers who financed the extension of the Paulista Company’s railway line. Then he goes quiet.

One clue as to what he might have been up to comes from the nickname he acquired—Boi—which appears in some reports of the murder. Other newspapers refer to him as Dr James Ox Warne, a translation of boi. It suggests that Warne became a rancher. This line of work did not enjoy a particularly high status in Brazil, whose planter elite collected their rents, sent their children to be educated in Paris and collected paintings by Poussin. For a man who had written a dissertation on oxygen, and whose father had owned a promising gold mine, such a fall in fortunes might have induced an attack of status anxiety.

In the decade following Warne’s arrival, Brazil faced problems similar to those that led the South to secede from the United States. From 1850 onwards, booming coffee plantations in the South had sucked in more than 100,000 slaves from the north-east. The coffee planters did not want to give them up. Once again the problem of how to compensate slave owners for the loss of their property stood in the way of abolition. Brazil found an ingenious solution. In 1871 parliament passed the law of the free womb, which stated that the children born to slave mothers would not themselves be slaves. Combined with the existing ban on fresh imports of slaves this set a deadline for abolition proper.

In 1885, two years before the murder, there followed a law freeing slaves between the ages of 60 and 65 in exchange for three final years of service. Few slaves lived that long, but the principle contained in the law was more important than its practical effects: the government could grant liberty to slaves against their masters’ wishes. By the beginning of the following year slaves were not waiting for the law to free them. They ran away in large numbers, daring the police to pursue them and enforce a law that much of the country now considered invalid.

São Paulo state, home to the great coffee farms, was at the heart of this conflict. Some police commissioners in the state enthusiastically pursued runaway slaves, who would then be beaten and sometimes tortured when returned to their masters, according to Karl Monsma of the Federal University of Rio Grande do Sul. Others chose to ignore the law. Among them was Araújo Cunha, the police delegado in Rio do Peixe. And so, when the mob beat down his door, Araújo Cunha must have known what they were after. The group was led, the police report says, by the local planters. They wanted their property back. “Bring the negroes out,” they shouted at Araújo Cunha’s house. When the delegado slipped and fell into the street below his tormentors shouted that he had cockroach blood, according to one newspaper. For some of those who mourned the passing of the antebellum South, the sight of a man with mulatto features like Araújo Cunha holding a position of power was maddening. Seized with a rage, fed perhaps by the accumulated disappointments of the past 30 years—the empty mine, the lost battles, the failed ventures in this new country—Warne hit his victim until he expired. One rather theatrical newspaper report written a couple of weeks after the murder adds that the doctor throttled Araújo Cunha “with sinister ferocity”. For those arguing for abolition, the crime provided a useful archetype of the wicked slave owner. The Revista Illustrada of February 25th 1888 reports that though the suspects had fled, “the world does not have a cave dark and deep enough to hide them.” The journalist was wrong. The police were reluctant to go after landowners and gave the mob enough time to slip away. A subsequent trial brought no convictions. As for Warne, dispatches from the United States’ consul in Santos, São Paulo’s port, report that at the beginning of the 20th century a Dr Warne and his wife were still living in the city whose name his crime had changed

The thought of the murderer living out a peaceful retirement surrounded by his family is unsettling. But the crime did not go entirely unpunished. Warne had travelled half way across the world to pursue a way of life that many of his contemporaries thought inhuman. At half-past three in the morning, in a small town in a foreign land, he had killed a man who interfered with his property rights, a policeman who would not enforce the law. Yet in doing so he helped kill the thing he loved. Three months after that night in Rio do Peixe, Brazil abolished slavery for good. It was the last country in the West to do so.