In the months since violence at a white-nationalist gathering in Charlottesville, Va., the national conversation has often focused on the history of white supremacy in the United States, and how much broader that history is in its impacts and geography than is often assumed. That aspect is highlighted in a new book about the Ku Klux Klan in the 1920s, The Second Coming of the KKK by two-time Bancroft Prize winner Linda Gordon, which puts modern anti-immigration and antisemitic rhetoric in context. In fact, though the KKK is best known for its racist attacks, other forms of hate have long been part of its history.

The first incarnation of the KKK formed just after the Civil War, using terrorist violence as a means of maintaining white supremacy, but its influence “waxed and waned,” as Gordon puts it, over the decades that followed. It was in the 1920s that the Klan was revived, its popularity spread through the infamous 1915 film Birth of a Nation, and soon became a truly massive social movement in the North, with some five million members. The Klan as it exists today is a more direct offshoot of the iteration that emerged during that time period in North, often in locations with very small African-American populations. What those places did have was a surge of immigrants coming to the U.S. in the late 19th century and early 20th century. Soon, the racist rhetoric of the original KKK was joined by anti-immigrant rhetoric directed at Catholics (accused of worshiping a Pope who sought to impose authoritarian rule), non-white immigrants like the Chinese and Japanese, and European immigrants not considered white enough, i.e. Italians and Eastern European Jews.

These new targets did not evolve unaided as part of the white-nationalist sphere. Rather, they were the result of a dedicated public-relations campaign designed to aid recruitment for the KKK, under the recommendation of public-relations professionals Elizabeth Tyler and Edward Clarke of the Southern Publicity Association, who advised the Klan to focus on drawing out prejudices that they suspected were already latent in American society. As a result of that decision, the new 20th century KKK was actually bigger in the North than it was in the South.

“At its peak, the Klan numbered between 3 million and 5 million people in the North,” Gordon explains. They recruited openly, publishing newspapers and magazines, promoting traveling lecturers, and holding state-fair-like “Klonvocations,” where members and their families would gather in the KKK’s infamous white costumes. “It’s estimated that 40,000 ministers were members of the Klan,” Gordon adds, “and these people were sermonizing regularly, explicitly urging people to join the Klan.”

In the early 1920s, the two states with the highest per capita Klan membership were Indiana and Oregon. Though Portland, Ore., has a reputation for liberal inclusiveness today, that was one of the cities where the KKK was most powerful. One major focus of Klan resentment in Oregon was on parochial schools, which were painted as part of the Pope’s plot to take over America. (Modern progressives may also be surprised to learn that the Klan called for a federal department of education at this time, because they wanted to be able to control curricula, Gordon points out.)

It’s worth noting that despite the anti-immigrant rhetoric that attracted Oregonians of the 1920s to the KKK, the state was overwhelmingly white and Protestant and 87% native-born in the early 1920s. The few Catholics and Japanese people that did live in the area were framed as threatening populations that could potentially grow bigger and take over the labor market if their presence wasn’t curbed quickly. “There were very, very few Catholics in Oregon, very few Jews and almost no African Americans,” says Gordon. “You can rev up hostility and fear even when there isn’t local evidence for that fear. My hunch is that many people in the Klan had really never met a Catholic.”

World War II dramatically changed Portland’s demographics, as it became a major commercial port and center for defense shipbuilding. With so many of the states’ residents shipping out with the Army, “defense industries became desperate for labor and paid to bring people in from other parts of the country,” says Gordon. “That’s what bought African Americans to Oregon. Then Portland became for the first time a diverse place, which it hadn’t been at all.”

It became even more diverse and cosmopolitan after the war, especially after Japan became a major manufacturer and began to ship more of its products into the U.S. through Portland, attracting a global business class.

The Klan’s biggest victory was its successful lobbying for immigration quotas, which were made law in 1924. The group got 16 members elected to the U.S. Senate, claimed it elected 75 to the U.S. House of Representatives and at least 11 Democratic and Republican governors to state houses. (Gordon notes that no one has been able to count all of the Klan candidates elected to state and local offices, as many non-members may have shared some points of Klan ideology.) But its newfound momentum was short-lived. In 1925, Indiana Grand Dragon D.C. Stephenson was convicted for kidnapping, raping and murdering his secretary, and the national press had a field day over the hypocrisy in a group that claimed to represent a Christian ideology. Membership fell from several million in the early 1920s to about 350,000 in 1927, and power struggles among leaders led some to split off and start rival groups.

After the deadly clashes in Charlottesville, hate groups in the Pacific Northwest have gotten renewed attention, as the Southern Poverty Law Center counts what it considers to be 21 hate groups in the state of Washington alone, concentrated especially in the Seattle area.

“The Klan has been flexible about who [its resentment] was directed at,” says Gordon. “In a sense, all bigotry is of a piece, all comes from the same sources of fear and anger.”

Write to Olivia B. Waxman at olivia.waxman@time.com.