On a balmy June evening in 1923, more than 25,000 men and women assembled in a rolling meadow to hear the message of the Ku Klux Klan. The speakers, dressed in their familiar white robes and pointed hoods, warned that Jews and Catholics were a danger to the nation. And a Protestant minister on the rostrum branded the Catholic Church “a political party in disguise.”

The rally did not unfold in Mississippi or Alabama or any of the former states of the Confederacy. The site was East Islip, on the South Shore of Long Island. The Ku Klux Klan was alive once again.

Most Americans who have seen or read “Gone With the Wind” associate the Ku Klux Klan with the years after the Civil War. The Klan had been founded by Confederate Army veterans in 1865 to perpetuate the culture of white supremacy in the South.

In the Reconstruction era, the hooded, white-robed night-riders terrorized former slaves, burned crosses, destroyed homesteads and lynched countless black Americans. The reign of terror subsided when Democrats regained political control in the South and used poll taxes and other means to exclude blacks from voting or running for office. The riders of the Klan, seemingly, galloped off into oblivion. But galvanized by the great waves of immigration from Europe about 1900, a new generation of Klansmen sprung up in Georgia in 1915 and spread to the North.

On Long Island, the “new” Klan adopted a law-and-order stance to attract recruits, backed Prohibition and criticized the “loose” morals of the times. By the early ’20s, men in white robes were burning crosses once again, this time at rallies on the outskirts of dozens of Nassau and Suffolk villages. Within a few years, historians estimate, one out of seven to eight Long Island residents was a Klan member — about 20,000 to 25,000 men and women.

Challenging the bootleggers, the Klan organized armed patrols to intercept illegal liquor along the shores and roads of Long Island, usually acting without police authority. After one skirmish, when rumrunners killed a Southampton constable, Ferdinand Downs, 2,000 Klansmen attended the officer’s funeral.

In contrast to its 19th-Century tactics, the Klan was hardly clandestine in the 1920s on Long Island. Often, respected clergymen and public officials openly supported the Klan and attended its rallies. On Sept. 20, 1924, for instance, the Klan drew 30,000 spectators to a parade through Freeport — with the village police chief, John M. Hartman, leading a procession of 2,000 robed men.

African-Americans were no longer the sole focus of the Klan’s message of hate on Long Island, because black citizens comprised only 2 percent of the population. Catholics and foreign-born Americans were a much more visible target. By 1920, foreign-born residents had grown to 20 percent of the population. In Nassau, the number had increased in two decades from 11,004 to 25,998. In Suffolk, the figure rose from 14,650 to 23,888. These new immigrants constituted “the greatest threat to the American way of life,” the Klan claimed.

Thousands of Long Islanders were drawn to the rallies to witness the fiery spectacle and to listen to the incendiary speechmaking.

On the night on Oct. 12, 1923, for instance, the Klan put on a pyrotechnic spectacular, burning crosses in a dozen villages across Long Island. Crosses were burned through the year in more than a score of villages including Freeport, Mineola, Bay Shore, Babylon, Riverhead, Huntington, Sayville, Garden City, Valley Stream and Hempstead. After an open-air meeting in Northport, a weekly newspaper observed: “A large percentage of the members of the Knights of the Ku Klux Klan of this village do not care whether people know who they are or not.”

Klan activities drew scant criticism from officials and private citizens alike. Many Long Island churches eagerly accepted money and other gifts from the Klan, and hardly anyone raised questions of political correctness when school boards welcomed the donation of American flags by KKK members.

Among prominent Klan members were James Zegel, the U.S. Treasury agent in charge of Bay Shore’s Prohibition-enforcement office who headed the Klan’s Islip “klavern,” or chapter. He held the title of Grand Exalted Cyclops. Maynard Spahr, popular pastor of a Methodist Episcopal Church, also held the grandiose title in Brookhaven.

Church trustees openly conceded that the Klan’s appearance in a community boosted attendance at Sunday services, and many ministers in the early 1920s were reluctant to ignore the opportunity. When Lynbrook Klan members presented the Church of the Nazarene in East Rockaway with a new silk American flag and a purse of gold, Pastor Paul Hill thanked the 40 Klansmen for their generosity, the Nassau’s Daily Review reported. A West Sayville clergyman, Andrew Van Antwerpen of the First Reformed Church, permitted a hooded Klansman to address his congregants. And William Norris, a Presbyterian pastor, exhorted members of his church in Bellport to vote for pro-Klan candidates.

The founding of one of Long Island’s first klaverns, in Freeport, was memorialized on Sept. 8, 1922, in the Daily Review, which carried a banner headline about the meeting at Mechanics Hall on Railroad Avenue. About 150 new members were greeted by seven robed Klansmen, the newspaper reported.

Journalists were permitted to sit in briefly because, as a “Mr. Smith” explained, their editors would surely “twist and distort” the true story. From the rostrum, Jews were the target of the robed speaker. “He was attacking the Jew — as an individual, habits, politics and method of living … He stated that two-thirds of the advertising in the papers was controlled by Jews,” the Daily Review reported.

Another account of a Klan presence ran in the Nassau Daily Review-Star when Klansmen staged a 1925 Memorial Day celebration in Hicksville, attracting 5,000 spectators: “A thousand men and women marched from a field east of Hicksville through the streets of the village and back to the field . . . in robes and hoods but with faces uncovered,” the newspaper reported.

While membership was spurred by the rising number of foreign-born residents, the Klan’s theatrics especially attracted older citizens, said Frank J. Cavaioli, a professor at the State College of Technology at Farmingdale. Speaking at a Long Island history conference in the 1980s, Cavaioli suggested that the Klan’s melodramatic activities served “as a counterweight to the dullness of life on rural Long Island.”

But by the mid-’20s, interest in the Klan cooled and cross-burnings became less frequent. Rivalries within the Klan’s leadership had taken a toll and, politically, the Klan had begun to slip. In 1926, when anti-Klan candidates won election in Greenport, Babylon and Sag Harbor, The New York Times observed: “Long Island seems to be recovering from its belief in the Ku Klux Klan . . . Thus has good sense returned to Long Island.”