How did this change affect people directly?
The invention of the cotton gin made cotton more profitable, meaning land and plantation owners got much more money. It also made the Southern states need more workers. "The most significant of these [changes] was the growth of slavery. While it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton. In fact, the opposite occurred. Cotton growing became so profitable for the planters that it greatly increased their demand for both land and slave labor." (www.archives.gov, 7) "...bigger cotton farms meant the need for more slaves. The slave population in the United States increased nearly five-fold in the first half of the 19th Century, and by 1860, the South provided about two-thirds of the world’s cotton supply. Southern wealth had become reliant on this one crop and thus was completely dependent on slave-labor." (www.civilwar.org, 3) This invention had many direct affects on people.
How did it affect the country?
This invention caused higher tension between the Northern and Southern states, and eventually helped lead to the start of the Civil War, and the end of slavery. "In terms of understanding what the cotton gin means for Civil War history, the connection to the growth of slavery and its economic centrality for the South is clear. Between the political conflict of the 1820s to 1850s regarding new states and slavery, the election of Lincoln, whom Southerners perceived to be anti-slavery, and the high tariffs imposed on cotton and cotton goods by laws written in the North, the fact that the cotton states of the Deep South chose to secede seems far less surprising." (www.civilwar.org, 4) As this quote tells us, the rise of market for cotton played a big part in the Civil War.
When did this change happen? Why did it occur? What else was happening at the time?
The cotton gin was invented in 1793, by Eli Whitney. It was invented because slaves needed a faster way to separate the seeds from the cotton. "...Whitney quickly learned that Southern planters were in desperate need of a way to make the growing of cotton profitable...The one variety that grew inland had sticky green seeds that were time-consuming to pick out of the fluffy white cotton bolls." (www.archives.gov) There were no major historical events or wars happening around the time of the cotton gin's creation, but we can still understand more about it by looking at some past. Near the time that this change occurred, Eli Whitney graduated from Yale College. He was thinking about going to law school, but instead started working as a private tutor in the South. He learned of the need for a faster way to produce cotton, and went about creating it. One interesting fact that I learned from my research was that many people believe(d) that Catherine Greene, Whitney's employer, greatly influenced the invention, giving both moral and financial support. "Whitney got the idea for the gin while working as a tutor near the estate of Catherine Greene in Savannah. Greene...also may have suggested some of the concepts behind the gin to Whitney, according to one 19th century author." (constitutioncenter.org, 3)
Did this change effect the North or the South more?
The cotton gin affected the South more because it caused them to be more dependent on their laborers. "As large plantations spread into the Southwest, the price of slaves and land inhibited the growth of cities and industries. In the 1850s seven-eighths of all immigrants settled in the North, where they found 72% of the nation's manufacturing capacity. The growth of the 'peculiar institution' was affecting many aspects of Southern life." However, despite the South being responsible for most of the excitement, both directions did end up getting involved.
How did this change affect westward expansion?
This cotton gin invention actually didn't affect westward expansion-- since the new issue of slavery arose, it didn't help people see why they should move from their homes in the east.