In american history who were the white ethnics?

Immigrants from Europe, is the right answer.

Explanation:

The term White ethnic is used to describe the descendants of settlers from Central, Southern and Eastern Europe, the Caucasus, Ireland and France etc. Basically, these were White Americans who were not White Anglo-Saxon Protestant. in short, they were European settlers whose customs and language differed from the original White Anglo-Saxon Protestants.

napoleon the third became a empire in 1873 also known as the era of the franco-prussian war.