At the height of its popularity, the Ku Klux Klan brought more than 30,000 of its members to participate in a parade in D.C. on Aug. 8, 1925. (British Pathé)

The Ku Klux Klan was at the height of its popularity when more than 30,000 members — racists and anti-Semites marching 22 abreast and 14 rows deep – paraded down Pennsylvania Avenue in Washington on Aug. 8, 1925.

“White-robed Klan cheered on march in nation’s capital,” read the front-page headline in The Washington Post the next day.

The gathering dwarfed the hundreds of white nationalists, Klan members and neo-Nazis who descended on Charlottesville Saturday to protest the removal of a statue of Confederate Gen. Robert E. Lee. The rally turned into a riot as the white supremacists clashed with counterprotests, leaving 32-year-old Heather Heyer dead and many others injured.

Nearly a century ago, the Klan was welcomed to segregated Washington by its white residents, as the breathless coverage in The Post demonstrated.

“Phantom-like hosts of the Ku Klux Klan spread their white robe over the most historic thoroughfare yesterday in one of the greatest demonstrations this city has ever known,” read The Post’s account.

Led by L.A. Mueller, the grand Kleagle of Washington, the Ku Klux Klan booked 18 trains for their march and rally. Hotels filled with the hooded men. Lunch stands and tobacco shops quickly sold out. The Klan even brought their own ambulances to escort those felled by the August heat.

The Post story rhapsodizes about their parade pageantry but says very little about the group’s espousal of hatred. However, it does criticize their parade skills: “There were few drilled marchers in the parade. At times their lines, extending the full length of the Avenue, swayed hopelessly back and forth.”

The effusive coverage of the Aug. 9, 1925 Klan march down Pennsylvania Avenue in Washington.

The Klansmen marched for over three hours before arriving at the Washington Monument grounds for speeches, only to be greeted by a torrential downpour.

“Don’t leave,” Mueller exhorted. “God won’t let it rain.”

But the rains came, washing out the demonstration, and many left.

The next day a Klan contingent crossed over the river to Arlington. They placed wreaths on the Tomb of the Unknown Soldier and the grave of William Jennings Bryan. That evening 75,000 people witnessed — many watching from roadsides and their back yards — the burning of an electrically lit 80-foot cross at the Arlington Park horse grounds. The ceremony initiated some 200 new members into the hooded order.

The Klan returned to Washington to parade again on Sept. 13, 1926. However, this time only 15,000 — less than half the previous year’s crowd — marched.

“To understand the prevalence of the Klan in the 1920s, try to imagine what the tea party on steroids would look like,” said historian Ibram X. Kendi, author of “Stamped from the Beginning: The Definitive History of Racist Ideas in America.” “That was the scope and power that the KKK had in the 1920s.”

Many of the hooded marchers showed their faces — a rather telling indication that the group, responsible for lynchings and other acts of terror, could operate with impunity. At the time, the Klan boasted a national dues-paying membership of nearly 5 million men and 500,000 women. The shedding of the masks was a subject of internal debate for the group, a move that some felt would grant their organization added legitimacy and respectability.

“You had many members of the KKK who were politicians — senators, congressmen, statehouse representatives,” said Kendi, “and that only encouraged the members to appear publicly without their hoods.”

Indeed, the 1924 Democratic convention was known as “the Klanbake,” because the party by a razor-thin margin voted against an anti-Klan plank in its platform.

“If you were a member of the Democratic Party, a powerful member, you probably had some sort of affiliation to the KKK either publicly or privately,” said Kendi. “Though there were also members of the Klan in the Republican Party, they had most of their power in the Democratic Party.”

The original Ku Klux Klan had fallen by the wayside after reconstruction, only to see its fortunes revived with director D.W. Griffith’s 1915 movie “The Birth of A Nation.” President Woodrow Wilson screened the film twice for guests at the White House.

The revived Klan drew its members not only from the South but from the Midwest and industrial North and saw itself as the protector of white Protestant supremacy. In addition to African Americans, they hated Catholic and Jewish immigrants and feared the Northern migration of African Americans.

They also saw themselves as great moralists. In additional to their campaign of terror against African Americans and ethnic minorities, the Klan broke up stills in the name of prohibition and flayed and flogged adulterers in the name of traditional family values.

Kendi sees parallels between the Klan of the 1920s and the alt-right that inspired the recent violence in Charlottesville.

“When you have a set of circumstances occurring, like those over the last 40 years — stagnating wages, immigration occurring, economic inequality growing — it allows demagogues to say this is occurring because of diversity, because of civil rights for people of color.

“These white supremacists are conditioned to believe this even though it flies in the face of facts.”

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