What is anglo-Saxon chauvinism?

It may mean nationalism and xenophobia of the 'anglo-saxons' or white anglo-saxon Americans. Chauvinism means nationalism and xenophobia, although its meaning has changed recently, in this case I'm sure it means xenophobia or even racism. The term suggests the nationalism and racism of so-called 'anglo-saxons' in 20th century America againist other ethnic groups, who they deemed inferior.