A huge collection of Ku Klux Klan material from the 1920s has been discovered, detailing the group’s “second coming” when it shifted from attacking blacks to Catholics and immigrants.

KKK robes catalog.

The enormous Klan cache, untouched since the 1920s, was found in Altoona, Pa., about 23 miles from Lilly where hooded Klansmen fought with Catholic German and Irish immigrants in 1924. At the time, 250,000 Pennsylvanians were members and all but two counties had KKK chapters.

It has been divided into over 40 lots and is being put up for auction next week by Maryland-based Alexander Historical Auctions. The total value is $20,000-$50,000.

“It’s a fascinating look at an evil organization which, like its mature grandchild today, tried to cloak itself in respectability to gain the support and funding of the ignorant and gullible,” said Alexander President Bill Panagopulos.

The collection includes hundreds of documents, letters, brochures, signs and outfits from the Altoona chapter of the KKK.

“The entire operation of the chapter is documented in the voluminous archive — rules, regulations, educational material, correspondence and uniform ordering forms for members of the Klan,” said Panagopulos.

It also includes material from "Women of the Ku Klux Klan,” and the "Junior Ku Klux Klan," which accepted boys from 12 to 18.

Of the more bizarre items are signs advertising "KLAN DAY" which included a picnic and elaborate fireworks display, a press release describing a baseball game between Klansmen and blacks.

The Klan began after the Civil War ended and later faded. In the 1920s it came back, but targeted immigrants and Catholics. That era has come into focus with the publication of “The Second Coming of the KKK —The Ku Klux Klan of the 1920s and the American Political Tradition.”

In the collection he’s auctioning, Panagopulos said “Of note is the fact that the there is little mention made of blacks — the primary enemy of the Klan was the ‘Roman Church.’”

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com