He worked as a cattle rancher, then in bridge and tunnel construction, before in 1874 becoming a marble cutter, settling in Iowa.
[1] Sovereign won the post, with the support of two key factions: populists based in the mid west, and socialists led by Daniel De Leon.
Sovereign promised to make the socialist Lucien Sanial editor of the union's newspaper, but when he did not follow through on this, De Leon's supporters withdrew en masse.
The following year, he began working for the Western Federation of Miners, as editor of its official newspaper, the Idaho State Tribune.
There, he joined a local affiliate of the American Federation of Labor, and served terms as both its secretary and president.