Final answer:
Migrants from the eastern United States embarked on various routes by boat, such as during the California Gold Rush where they sailed to Panama and onward to San Francisco, or followed the coastal route into the Western Hemisphere based on the kelp highway hypothesis. Increased transportation infrastructure later eased American westward expansion.
Step-by-step explanation:
Individuals who travelled by boat from the eastern United States during various periods of migration took multiple routes depending on their final destination and the era. For example, during the California Gold Rush, Easterners seeking instant wealth sailed around the southern tip of South America or to Panama's Atlantic coast, where they crossed the Isthmus of Panama to the Pacific and then took passage to San Francisco. Before the War of 1812, in the early 1800s, travel was typically done using roads, canals, and coastal shipping, which was inefficient and expensive. Improvement in infrastructure such as roads, canals, and railroads later facilitated the westward movement of Americans from the eastern coastal states.
The coastal route was a significant migratory path posited by the kelp highway hypothesis, suggesting early populations travelled by boat along the Pacific coast into the Western Hemisphere. This was around 15,000 to 18,000 years ago and might have extended as far south as Chile. Migration trials like these have always impacted the countries involved, affecting their social, political, and economic life. During the period of American slavery, those seeking freedom from the eastern states would often use water routes to escape, taking advantage of the lessened risk of being stopped or identified as runaways.