Why white supremacists carried medieval signs in charlottesville?

from the medievalist academy blog:

'Contemporary white nationalists are not the first Americans to have turned nostalgic views of the medieval period to racist purposes. It is, in fact, deeply ironic that the Klan’s ideas of medieval knighthood were used to harass immigrants who practiced the forms of Christianity most directly connected with the medieval church. Institutions of scholarship must acknowledge their own participation in the creation of interpretations of the Middle Ages (and other periods) that served these narratives. Where we do find bigotry, intolerance, hate, and fear of “the other” in the past—and the Middle Ages certainly had their share—we must recognize it for what it is and read it in its context, rather than replicating it.'

it refers to race, i am pretty sure this was a popular term in nazi germany or something.