You mean the other Christians. Mormon men wanted to marry multiple wives, the other denominations said no fuck you to one denomination. They are all Christians.
In law, we still place our hand on a Bible and swear by it, etc. The difference is just that Catholics and Protestants and whoever else were already dominant in society when Mormonism arose, and the other Christians were threatened by that and were like like nah bro you aren't real Christians we run this land get fucked like all the other minorities