What were the challenges that slaves faced during 1775-1830?
The Revolutionary War presented more of an opportunity than a challenge for slaves, as the British offered freedom to any slaves who chose to flee to their side. Even so, they were not taught to read or write, and probably knew little of the ramifications of the war. The Cotton Gin in essence rejuvenated the institution of slavery at a time when it was slowly dying away; but I am not sure that it caused a greater instance of slaves being "sold down the river."
In actuality, the major problem they faced was the institution itself. They were forced to work from "kin to kin't" (literally sun-up to sun-down,) could not leave the plantation without a special pass, and had no rights whatsoever, including the right of marriage, unless their owner saw fit to allow it. They were also subject to the whims of the Master and Mistress of the house, and young female slaves could expect to be sexually assaulted by any males in the house, particularly younger men. There was the continued threat of forced separation which occurred with uncomfortable frequency; and in most states, a master could lawfully kill his slave, as the slave was his property which he was allowed to destroy if he so chose. Although the attitude of many white Americans toward slavery changed because of the Revolution, particularly in the North, it presented no particular "problem" to slaves.
Of course, slaves at all times in the United States (and the colonies) faced many challenges. These are the obvious challenges like having to work hard without pay in harsh conditions. But since you ask about this particular time period, let me discuss two challenges that would have been somewhat unique to that period.
First, there was the Revolutionary War. Slaves had to face a psychological challenge here. They had to deal with the fact that the country they lived in was fighting a war for freedom while some of its greatest patriots held them in slavery. This would have been psychologically difficult because they would have been hearing talk of freedom and independence while being kept in slavery themselves.
Second, there was the invention of the cotton gin. This led to a massive shift in slavery from the Upper South to the Lower South. This meant a wave of slaves being sold "down the river." More than at other times, slaves were faced with being separated from their families and homes.
Slavery was always difficult, but these were two challenges that were more prominent in this time than in others.
The slaves suffered through a lot back then. They got whipped, and they were treated like dirt.
For more info on slavery:
Watch "ROOTS" by Alex Haley
Well slavery had many challenges , but the point you are talking about was during the Revolutionary War. There were those that offered freedom to the slaves if they helped the British in the war. The slaves however could not read or write so that was a great challenge to them as they did not understand the ways of war. Then there was the fact that a slave had no rights and could not just leave a plantation without special papers that had to be drawn up for them, and they had carry them always. This was incase they ran into a slave trader or slave hunter. Then there was the fact they had to work from sun up to sun down with little food or rest. And at anytime they could be sold without cause to someone else, or their children could be sold to others and there was nothing they could do about it.