The Klan did not really disappear from Oregon.  They are still here, just not as visible (no headquarters).  Many have also melded into different hate groups.  We have a multitude of white supremacist groups here, all who had their start with the KKK.  Portland and Eugene have headquarters for some of the most vocal hate groups, including white nationalists, black separatists, and general hate groups.  There are a lot more than what are nationally recognized.  https://www.splcenter.org/hate-map