Harriet Hamilton Pier was born on April 26, 1872, in Fond du Lac, Wisconsin.

Mother and daughters constituted a law firm practicing first in Fond du Lac and then, in 1888, in Milwaukee, Wisconsin.

[6] Pier entered the law department of the Wisconsin University, and, at the end of two years, she took her degree of LL.B.

[4] In 1891 Caroline and Harriet were admitted to the bar, alongside their mother and sister were four of the eight female lawyers in Wisconsin.

She had much experience in and about the pine forests of northern Wisconsin and had actual personal charge and management of large tracts of timber land.