Today marks the centenary of the Carnegie Klan Riot, aptly named to describe what happened that time the KKK got it into their heads to march through the heavily Catholic town of Carnegie, just outside of Pittsburgh. Their aim was to stick it to the papists, who were also overwhelmingly Irish immigrants and thus doubly objectionable. Things didn’t, as the word “riot” will have alerted you, go well for their little racist pajama party.