Many abolitionists regard the immediate cause of…
May 1856 CE
Lawrence residents had driven Jones out of town after they shot him, and on May 11, Federal Marshal Israel B. Donaldson proclaimed that the assassination attempt had interfered with the execution of warrants against the extralegal Free-State legislature, which was set up in opposition to the official pro-slavery territorial government.
Donaldson's proclamation and the presentment by the first district of Kansas's grand jury that "the building known as the 'Free State' Hotel' [sic] in Lawrence had been constructed with a view to military occupation and defence [sic], regularly parapetted and port holed, for the use of cannon and small arms, thereby endangering the public safety, and encouraging rebellion and sedition in this country" lead to Sheriff Jones and Marshal Donaldson assembling an army of roughly eight hundred southern settlers.
This group plans to enter Lawrence, disarm the citizens, destroy the anti-slavery newspaper presses, and level the Free State Hotel.
A number of men from Texas and South Carolina join Donaldson and Jones's posse.
On May 21, 1856, while this group is camping a few miles west of Lawrence, David Rice Atchison gives a speech to these men, promising that they will be "well paid" for their service and that they are working for "the present administration".
They are there for "the entire South" and the goal is to spread slavery, and stop anti-slavery newspapers in Lawrence.
Atchison promises that he will lead them into this battle, and makes them all cheer as a promise to draw blood.
He also mentions that the flag he rides under is the red flag of the South—red for the color of blood they will spill.
Elsewhere, Atchison had promised to see Kansas in Hell before he let it become a free state.