White men captured slaves and forced them on ships for months that were unbearable, crawling with disease.
Once the former slave became a US citizen they were still segregated and not allowed to vote (even though the constitution says no state shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any state deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.) and were humiliated or attacked in public.
They were whipped and spent 10-12 hours in the blaring sun working on the plantations, they were also not allowed to marry, parents would be separated from their young kids and most of them never saw each other again.