Final answer:
Pre-Civil War, the North saw significant industrial growth with the advent of railroads, the steamboat, and inventions like the telegraph and sewing machine, in stark contrast to the South's agricultural economy based on slave labor. These economic developments contributed to increasing sectional tensions between the North and South.
Step-by-step explanation:
Before the American Civil War, the Northern United States experienced significant economic developments, distinguishing it from the agriculture-dominated South. Major industries flourished, especially with the advent of the steamboat, which utilized large rivers for transport. The telegraph drastically improved communication across states, and the sewing machine facilitated the mass manufacture of clothing. These advancements were critical as most industrial factories were located in the North, in contrast to the Southern reliance on agricultural plantations and slave labor.
The railroads played an integral role in economic expansion, helping to unify distant regions and contributing to westward growth. They also inadvertently hastened the displacement of Native Americans. In the North, technological innovation and entrepreneurship thrived, bringing about a multitude of new products and machines. Deep-seated economic differences between the North and the South, compounded by conflicts over tariffs and federal policies, heightened the sectional tensions that eventually led to the Civil War.