The pivotal moment in U.S. history that led to the establishment of the Social Security Act was the Great Depression, which began in 1929. This severe economic downturn resulted in widespread unemployment, poverty, and suffering among Americans. The federal government recognized the urgent need to provide support for the elderly, unemployed, and disabled. In response, President Franklin D. Roosevelt introduced the Social Security Act in 1935, creating a social insurance program designed to offer financial assistance and help stabilize the economy. It marked a significant shift towards a welfare state and established the foundation for the modern social safety net.