Generally speaking, "assembly line jobs" did not represent an obstacle during this time, since this in fact increased productivity through the "specialization of labor".
The cotton gin was innovated by Eli Whitney and is important to the 1800d because of what it did to the innovation of cotton production in the south. Prior to the machine, enslaved people were forced to hand process cotton, now with the machine, more cotton was able to be processed faster which allowed for slavery to continue and expand in the south so that more cotton could be sold to Britian (who did not have the land for cotton growing) and the northern factories to be made into clothes (increasing production of the industrial revolution especially with the Lowell mills). This will be important later with the Civil War as the south believes that Britian will support them because of their trading history and need for cotton (which of course is not done, due to racial tensions between the newly freed persons of Britian and the enslaved system of the South).
Ellis island was where thousands of immigrants were processed before being allowed into the United States.
When the Nazi's fled and the Russians (I believe) invaded was a huge turning point giving jews and all others captured, hope and freedom.
