This happened in the 1930s. Are you familiar with what the Abolitionist Movement is? This is a movement that was done to stop all forms of slavery that were highly rampant at that time. Some slaves were being traded from one continent to another.
They were brought to different countries through ships, and some of them were never able to set foot outside the houses of their masters again. The movement was meant to set the slaves free. They have argued that making other people their slaves mainly because of their skin color is a sin.
The answer to this question is 1830. This is the type of move that was done in order to abolish slavery. There are some people who use the term abolitionism in order to end formally and informally. There are some people who have become frustrated with the slow pace of the abolition of slavery even if it was already announced and people thought that change was going to come.
There were different people who were involved in this movement such as Frederick Douglass, Harriet Beecher Stowe, and William Lloyd Garrison. These were the people who were behind this movement in order to end slavery.