The south's main concession to the north in the compromise of 1850 was: acceptance of popular sovereignty in the new mexico and utah territories
the fugitive slave proposal
the admission of california as a free state
the admission of texas as a slave state

In the Compromise of 1850 to the North California was admitted as a free state and at the same time, California agree no to interfere or regulate in the areas or parts that Mexico held inside the state. Also, California wanted to have a better understanding and enforcement by the North of The Fugitive Slave Act which allowed the North to keep and retain escaped slaves with the conditions that they would be returned at a later date to their proper owners in the south. The act in itself was very controversial.

Furthermore, California also agree and guaranteed that Utah and New Mexico would not have any federal restrictions on slavery. Other States were also affected like Texas which lost all boundary claims the state had against its neighbor New Mexico. The State of Texas was not very worry about this because in a later date Congress compensated Texas with a $10 million payment.

As a whole, slavery was still maintained in the nation´s capital, but at the same time trading slaves was prohibited. We most remember that the United States was in its infancy, and many of the decisions made at the time will not be seen as efficient now, but they made sense at that time.  

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