Before slavery in colonial America became completely based on skin color, thousands of African slaves served European colonists together with white and Native American slaves. Sometimes, after working off the slavery period, negros received freedom and land allotment, that is, they became landowners. In 1676, Nathaniel Bacon began an uprising against the exploitation of poor colonists by rich landowners. The uprising could not be called successful, but after his death, the revolution lost the leader from the disease, but Bacon received wide support among the slaves, and as a result, they nevertheless achieved that now only negros could be used as slaves, while white was promised different benefits . These decisions marked the beginning of a long period of “black slavery”, when blacks were used for agricultural work, especially in the production of cotton and tobacco in the southern states. But years later Abolitionists started trying to make slavery illegal in the mid-1700s. By 1804, all of the northern states had ended slavery. However, none of the Southern states had. The Southern states believed that slavery was their right, and they did not want to give it up. Cotton had become a very important crop in the South. Owners of large cotton plantations were used to having slaves to do work for free, which made the plantation owners richer because they did not have to pay anybody to work.

Eventually, the South tried to leave the United States. This caused the American Civil War. The North won, and in 1865, the Thirteenth Amendment to the United States Constitution made slavery illegal everywhere in the country. In 1868 and 1870, the Fourteenth and Fifteenth Amendments gave African-Americans citizenship, and gave them the right to vote.

However, the life of blacks did not become easier after all. That's how the process of segregation started.

Of course, nothing can make people, who have never considered blacks to be normal human beings, perceive them as equal to whites, not even war.

They still saw them as property, and simply could not accept the fact that blacks had rights as well. That’s why starting in 1890, the all-white legislatures in the Southern states began to pass state laws that required segregation. These racist laws became known as Jim Crow laws.

According to these laws’ blacks could not:

• Visit the same public places as whites (cinema, theaters e.t.c.)
• Use the same common objects (like drinking fountains or toilets)
• Sit next to white people in public transport 

In 1896, in a case called Plessy v. Ferguson, the Supreme Court ruled that these laws were legal. They said that segregation was fine, as long as things were "separate but equal." In the South, everything was separate. However, places like black schools and libraries got much less money and were not as good as places for whites. Things were separate, but not equal.

Segregation kept African-Americans from having the basic rights that the Founding Fathers had written into the Constitution of the United States. Law-makers, government officials, voting officials, and police officers were all white. This prevented African-Americans from having any say in their government; being able to get the same voting rights as white people; having police officers protect them; or being able to get justice for crimes against them. Because they could not count on all-white police forces to protect them, violence against African-Americans, especially lynchings, increased.Because African-Americans could not vote, they also could not serve on juries. This meant that if a black person was ever on trial for a crime, the jury would be all-white.

African americans suffered from segregation for many years and finally decided to fight for their rights and thats how the Civil Rights movement started. 

American civil rights movement - mass protest movement against racial segregation and discrimination in the southern United States that came to national prominence during the mid-1950s. This movement had its roots in the centuries-long efforts of African slaves and their descendants to resist racial oppression and abolish the institution of slavery.

Through nonviolent protest, the civil rights movement of the 1950s and ’60s broke the pattern of public facilities’ being segregated by “race” in the South and achieved the most important breakthrough in equal-rights legislation for African Americans since the Reconstruction period (1865–77).

Although the passage in 1964 and 1965 of major civil rights legislation was victorious for the movement, by then militant black activists had begun to see their struggle as a freedom or liberation movement not just seeking civil rights reforms but instead confronting the enduring economic, political, and cultural consequences of past racial oppression.

Officialy - the success of this movement is considered to be the end of racism and discrimination, however it is not try and even today there millions of african americans, who suffer from this ancient prejudice.

https://www.britannica.com/topic/racial-segregation


https://www.history.com/topics/black-history/civil-rights-movement