Robert F. Bukaty / AP

If U.S. politicians’ love affair with tariffs seems novel, it’s really the latest installment in an on-again, off-again romance. And it’s one that has been much more passionate in the past. In the decades after the Civil War, the “tariff question” was the biggest issue in American elections. On everything from wool to sugar, the U.S. government slapped steep fees on goods passing through its borders. These tariffs protected domestic industry and paid the government’s bills.

But sometimes tariffs also led to trade wars with America’s neighbor to the north. Today, America and Canada fight over dairy and aluminum. In the late 19th century, they fought over frozen herring—and these trade wars meant real violence. When T. Aubrey Byrne alighted from his train in Gloucester, Massachusetts, on the last day of 1894, he stepped into the middle of one such war.

Depending on who you asked, Byrne was either the Treasury’s best special agent, a man who had saved the government fortunes by uncovering massive smuggling rings—or he was a failed ranch hand and ex-newspaperman, a paranoiac who saw fraud in others’ honest toil. But his superiors at Treasury approved of the job he’d done breaking up operations to illicitly import sugar and Chinese laborers. Now Byrne sniffed another conspiracy: a plot by merchants and captains in Gloucester, the capital of New England fishing, to avoid taxes on fish from Newfoundland.

Every winter, a fleet from Gloucester sailed to the island—still a British colony—to fill their holds with frozen herring. At less than a cent apiece, herring would be eaten by humans or used as bait for the more lucrative cod and halibut fisheries. Starting with one entrepreneurial vessel in 1855, by the 1890s almost 100 ships each year went to Newfoundland from Gloucester. And each year tens of millions of spawning herring swam into the bay only to sail out of it.

Under treaty terms in effect from 1873 to 1881, American fishermen had the right to fish for herring in Newfoundland’s coastal waters. Whether these fish were taxed back in Massachusetts, however, depended on who had plucked them from the water and performed the labor of freezing them on deck. If Americans did the work, catching huge numbers of herring in weighted nets called seines, the fish were American too and therefore tax-free; if the captain hired Newfoundlanders or simply bought already frozen fish from locals, then each herring was subject to a hefty tariff.

When the customs collector at Gloucester declared that all 30 million herring unloaded there in 1894 were tax-free American fish, the Treasury smelled something rotten. Newspapers reported that Byrne sent an inspector undercover with the Newfoundland fleet, and the inspector confirmed that the Gloucester fishermen were not fishing at all. Instead, they were “using dollars as bait,” as one newspaper put it—buying their fish from the locals and avoiding taxes by filing false paperwork.

An 1887 engraving of Newfoundland fishermen published in Harper’s Weekly, based on sketches by J. W. Hayward (Library of Congress)

For decades, the New England fishermen had complained about the difficulties of fishing off Newfoundland. They would much rather fish fish than buy fish, they said, but they purchased the herring because the “natives” of Newfoundland forced them to. In popular publications and official government reports, 19th-century Americans described the Newfoundlanders in terms they usually reserved for darker-skinned people who lived in places the U.S. planned to invade and colonize: illiterate and half-naked subsistence farmers, incapable of understanding capitalism or accumulating wealth, who “flocked aboard” approaching U.S. vessels in the hopes of an invitation to dinner. They had to be watched while on board, American captains warned, lest they ransack the ship and steal whatever they could, and if the captains did not hire them to do the fishing, they would retaliate against vessels and crew. That was exactly what these captains alleged had happened in January 1878.

That winter was remembered on both sides as a bad one for the Newfoundland herring fleet—the fish were small and scarce, and unusually warm weather made it difficult to freeze them on deck. In December 1877, the first of more than two dozen Gloucester ships had arrived in Fortune Bay, in the island’s southeast. But the herring kept the fleet waiting: By Saturday, January 5th, there were still no fish in the bay. On the 6th, the herring appeared at last, and the Americans, eager to bring the first cargoes back to New England, began to lay their seines.

Witnesses on board the ships testified later that over two hundred Newfoundlanders “gathered on the beach and demanded that the seines be taken up, giving a pretext that it was unlawful to fish on the Sabbath.” This crowd then began, the Gloucester shipowner John Pew attested in a petition to the Treasury, “a war-like demonstration.” They overpowered the crews, tore up Pew’s seines, and liberated all the herring. Afterwards, the islanders made what one captain called a “jubilant demonstration” on the shore, “firing guns, blowing horns, and shouting, as if celebrating a victory.”

The British observers saw these events differently. The law prohibited fishing on Sundays, so Newfoundlanders could not have worked no matter what their religious beliefs, and understandably they did not want to see blasphemers make off with all the herring. Even so, the situation had been peaceful, the British foreign secretary explained to his American counterpart, until an American captain pulled out his revolver. What everyone agreed was that by Monday morning, January 7th, the herring had slipped away.

The events that day—which U.S. President Rutherford B. Hayes called an “outrage upon American fishermen”—set London and Washington at odds for years and scuttled attempts to negotiate a new fisheries treaty. In 1887, in retaliation for years of piscine slights, Congress even granted the president power to eject British and Canadian vessels from U.S. waters. The British eventually paid millions to the Gloucester fishermen in compensation for the fish Pew and others claimed had been lost.

But the memory of injustice lingered, and the Gloucester residents gathered on the customhouse steps on New Year’s Eve, 1894, were not happy to see the Treasury poking into their business. Byrne came to Gloucester to confront the town’s customs collector, William Pew—the son of the merchant whose nets had been wrecked—who refused to cooperate with his inquiries. The special agent accused Pew, a fellow Treasury officer, of being in league with the smugglers, and two neutral customs officials were called in to arbitrate. In this impromptu court, half a dozen captains admitted to paying Newfoundlanders by the hour, the barrel, or the shipload. In his defense, Pew supplied affidavits claiming that the 30 million herring he had waved through customs were taken directly from the water by Gloucester’s fishermen. Byrne had just as many saying they were frozen on the beaches by Newfoundlanders.

Each side accused the other of conspiring with nefarious outsiders. People in Gloucester, a town whose fortune was always precarious, saw Byrne and the Treasury as stooges of Big Herring in New York and Boston, set up to drive their fishermen out of business. Pew himself, whom the town considered a “doughty champion of the fisheries,” even accused Byrne of being manipulated by a Canadian secret agent, who allegedly disguised himself as the correspondent for the Associated Press while working for the fishing interests of Newfoundland. Papers in the big cities, meanwhile, portrayed a corrupt “fish combine” in Gloucester whose method was to cast aspersions on the Gilded Age deep state.

After a few days of testimony, the arbitrators rendered their verdict: The fish were foreign, and the fishermen had to pay. Pew was replaced as customs collector by an independent outsider. And whether because taxes meant higher prices or simply because of fickle demand, the next winter the herring market froze up. Twelve million unsold fish sat thawing aboard ships in Gloucester harbor, while the public, The Boston Daily Globe gloated, had given frozen herring “the cold shoulder.” Across the ocean, meanwhile, Newfoundland’s government exhorted its fishermen not to sell at any price. “Newfoundlanders, be men!” one sign said. “Starve if you must: but hang on to your herring!”

Today, just as in the 19th century, tariffs are rarely made by technocratic economic calculus. More often, they’re judged by whether the benefits accrue to the “right kinds” of people—hardworking Gloucestermen or “primitive” islanders, law-abiding subjects or Sabbath-breaking foreigners. And trade wars can pit fellow citizens against each other just as often as they unite them against an enemy. Metal tariffs may enrich some American companies—or just their executives—but everyone will soon pay higher prices for manufactured goods. Presidents pick fights, while wealth swims out to sea.