Secret Anti-Catholic Societies

While reading on the background of Father James E. Coyle I found that the KKK worked alongside a secret society called the True Americans in Birmingham and caused civil unrest. After searching for information on this group, there really isn't much there on this particular organization. During the late 1800's, anti-Catholicism and anti-immigration reached a fever pitch. How hard it must have been for immigrant Catholics at this time. How many may have converted our of fear? We may never know. The following are some links I found in my search. I've always been a history buff and have recently found some wonderful sources for early Catholic life and history in the US. I suppose the events of my childhood still have me puzzled and without closure on the thought of any "group" who was blatantly anti-Catholic.

American Anti-Catholicism and its Literature
The American Protective Association
World Religions and 101 Cults and Sects
AMERICAN PARTY

This link, while interesting, is full of errors regarding Catholic organizations(some of which are not even "secret"):
Secret Organizations