With slaves, the enslavers split up families, languages, religions and cultures into groups. Over a hundred years, the slaves have adopted the language, religion, and culture of the enslavers. The African-Americans who are descendants of the slaves have lost their origins. One of the worst things done by man.

As I understand it, in the USA Christianity was forced on the slaves with the promise that suffering in this life was a blessing, and would result in greater rewards in the next, that the chance to be slaves in a Christian country was a blessing since they could hear and accept the gospel and be saved, unlike those left behind in heathen savagery.
In short the con of jam tomorrow is worth plain bread today, and plain bread today is better than starvation yesterday.
Since those who accepted this shit "prospered", that is were allowed to have children, got feed and were not beaten to death and those who did not died in great pain, a few generations of this lead to a pliant, readily obedient populous accepting the "normality" they were born in to.

Look I'm a Brit or Limey as you sometimes call us. We both invented and outlawed the slave trade, a part of our history that saddens me deeply. Yes there still racism here but thankfully far far less. I went to a gospel church in east London many years ago, I was welcomed with open arms and the music was fantastic. So for me the answer to your question is the coming together of people and the kindred spirit that binds them.