Need help to find a Historically controversial issue from pre-20th century. >followed by a how question about the issue.

Which country?

Any country instead of the U.S. 20th century

What do you mean by "historically controversial issue", please? There is also the following search that you might want to try. Historically Controversial Issues - Google Search (http://www.google.com/search?hl=en&q=Historically+Controversial+Issues)

Taxation without representation, slavery... think about why some wars were fought.