White sheets in Washington, D.C."The “secret” society had 3 million members during its heyday in the early 1920s; roughly half its members lived in metropolitan areas, and although it enjoyed considerable support in the South, the Klan was strongest in the Midwest and Southwest. In this photograph, forty thousand members of the Klan march down Pennsylvania Avenue on August 8, 1925. Organized to counter reports of faltering enrollment, this “konklave“ succeeded in attracting national attention but marked the peak of Klan power in the 1920s. " History Matters - GMU