Final answer:
Tenant farming emerged as a survival strategy for many farmers due to cyclical debts, foreclosures by banks, and predatory practices from wealthy landowners, leading to loss of land and livelihood, especially during periods of economic downturn or poor harvests.
Step-by-step explanation:
Tenant farming became the only way for many farmers to survive due to a combination of environmental, economic, and social factors. For farmers, especially those during the Han times, debt cycles were a significant contributor to their vulnerability. Farmers relied on producing a successful harvest to pay off debts accumulated through the year for seed, equipment, and land. However, a poor harvest or calamitous event could plunge them into inescapable debt.
In places like the Great Plains during the Great Depression, foreclosures by large eastern banks were common as drought and low commodity prices meant farmers couldn't pay their debts, ultimately leading to the loss of their farms. Similarly, in ancient societies such as Rome, predatory practices by wealthy landowners forced small farmers off their land. Systems of credit during times of hardship, such as post-war periods in the South, further strained farmers, leaving them 'land poor' with little cash to afford necessities.