What did the White League want?
The White League was organized to intimidate freed slaves and keep those who supported those ex-slaves out of office.
The White League paramilitary organization started in 1874, soon after President Abraham Lincoln issued to Emancipation Proclamation in 1863 that called for all slaves to be released. This was the response from angry slave-owning or slave-benefiting residents in Confederate states, for it started with many Confederate veterans who served during the Colfax massacre, where about 150 black men were killed by white southerners.
This group of white men (hence the name) wanted to eliminate all of the progression the northerners were doing to emancipate all of the slaves. They preferred pro-slavery candidates to run for office. At this time, the south is considered Democrat and the north is considered Republican. (This isn't to be confused with how in modern times we see more Democrats up north and Republicans down south.)