The Boston Marathon bombing was the first major terrorist attack on American soil since 9/11. Even so, bombings are nothing new in the United States—not even to Boston. Almost 100 years ago, the country was besieged by violent anarchists intent on bringing about the end of capitalism and organized government. In Boston, bombs went off at a police station and at the homes of political figures, with the goal of sowing fear and discord toward some vague political aims. This political ferment was the backdrop for Dennis Lehane’s 2008 novel The Given Day. But the truth of the era might be stranger than fiction.

Though today you know anarchists as the disheveled, harmless black-clad youth most often found chanting during WTO protests, anarchists were near the top of the American government’s enemies list a century ago. Many of these anarchists were based in or around Boston. As Steve Puleo wrote in his book The Boston Italians, by 1916, Boston’s North End had become “the headquarters for some of the leading Italian anarchists in America, men whose primary persuasive tools were terror and violence.” These Bostonians wanted to persuade their fellow countrymen that capitalism and organized government were the primary enemies of workers and the poor. They had more specific complaints, too. Just as alleged Boston marathon bomber Dzhokhar Tsarnaev claims he and his brother Tamerlan were inspired by American military involvement in Iraq and Afghanistan, the anarchists were incited by the United States’ eventual involvement in World War I.

Their leader was Luigi Galleani, an Italian immigrant based out of Lynn, Mass. In the pages of his newsletter, Cronaca Sovversiva, Galleani preached resistance to authority, by violent means if necessary.* (Galleani also wrote a bomb-making manual called La Salute è in voi! that was “an Italian language manual for the manufacture of dynamite and other weapons to be used in the upcoming class war.”)

Galleani’s followers took this advice to heart—and the Boston area faced the consequences. On New Year’s Day 1916, a suitcase filled with dynamite was discovered in the Massachusetts State House; the suitcase would have exploded if not for a defective fuse. The next day, Puleo writes, a bomb destroyed a factory in nearby Woburn, Mass. The rest of the year was relatively quiet, but in December 1916, a couple weeks after several local anarchists had been arrested at “a violent anti-military preparedness riot,” dynamite went off in the basement of a police station on Salutation Street, in the North End. Though no casualties were reported, the blast wrecked much of the station and shattered windows across the neighborhood; Puleo writes that “eighteen to twenty sticks of dynamite had been used to fashion the massive bomb, and that the explosion could be heard and felt across the harbor in East Boston.” The bombers were never captured.

Three years later, anti-government bombers struck again. North End anarchists began the year by posting signs all over Commercial Street, deriding the “senile fossils ruling the United States” and vowing, “We will dynamite you.” Five days later, when a molasses tank collapsed and flooded North End streets in a sticky tide, killing 21 people, many thought Italian anarchists had dynamited the tank. (They had not.)

On the night of June 2, bombs were set off in several cities across the country, timed to explode around the same time. Two went off in Boston, one at the house of Judge Albert Hayden, the other at the house of state Rep. Leland Powers. Hayden had delivered stern sentences to some anarchists who’d been arrested for parading on May Day, while Powers was likely targeted for having introduced a harsh anti-sedition bill to the state legislature, which was passed five days before the bombs went off.

Nobody was killed in these two bombings; the only person injured was Powers’ young daughter, whose cheek was cut by some shattered glass. In fact, only two people were killed nationwide, one of whom was an anarchist who died when the bomb he was trying to place exploded in his face. (It seems that, for all their rhetoric, the Galleanists were rather inept bombers.) But the bombs still sent a message—one that was underlined by the handbills left at every bomb site, signed “The Anarchist Fighters”: “There will have to be bloodshed; we will not dodge; there will have to be murder: we will kill, because it is necessary; there will have to be destruction; we will destroy to rid the world of your tyrannical institutions.”

The government reacted strongly against the anarchist threat. Though he had no direct connection to the attacks, Galleani was deported to Italy a few weeks later. Attorney General A. Mitchell Palmer, whose Washington, D.C., house was targeted by the June 2 bombers, coordinated the federal response to the June 2 bombings. First, he put a 24-year-old Department of Justice clerk named J. Edgar Hoover in charge of the DOJ’s General Intelligence Division, tasked with investigating domestic radicals.

That November, Palmer and Hoover had federal agents and local police officers round up immigrants suspected of being involved with radical causes, with an eye toward their eventual deportation; these sweeps became known as the Palmer Raids. It was the first real Red Scare in this country, and, as eventually happened with Joseph McCarthy in the 1950s, public opinion eventually turned against Palmer and his raids. As Lehigh Ph.D. candidate Joshua Britton writes, “American citizens had been detained, many aliens had been arrested without a warrant and there were dozens of cases of mistaken identity. The treatment the detainees endured was particularly harsh and included beatings, inadequate space, sanitation, and rations for the prisoners.”

After all that, only two men were arrested in connection with the June 2 bombings. What’s more, the Palmer Raids weren’t particularly effective in stopping future bombings: In 1920, a horse-drawn cart laden with dynamite and sash weights exploded outside New York’s City Hall, killing 38 people and wounding at least four times as many. Though the crime was never officially solved, historians believe Italian anarchists were responsible.

Correction, April 26, 2013: This article originally misspelled Luigi Galleani’s newsletter Cronaca Sovversiva. (Return to the corrected sentence.)