I was astonished when I first learned that in the United States, it wasn't until partway through the 20th Century that people of Italian or Jewish ancestry were considered "white."
https://www.google.com.au/search?q=irish+need+not+apply&sour...
here's where the "myth myth" started and was easily debunked by a high school student
http://www.irishcentral.com/roots/history/High-school-studen...