The leading cause of the 1929 stock market crash that precipitated the Great Depression was excessive speculation and a lack of regulation in the financial markets. Throughout the 1920s, stock prices soared, driven by widespread optimism and easy credit. However, underlying economic weaknesses, including overproduction, rising unemployment, and unequal wealth distribution, created an unstable environment. When confidence began to wane, panic selling ensued, leading to a dramatic decline in stock prices. The resulting crash eroded savings and triggered a systemic economic collapse, ultimately affecting millions and leading to significant changes in financial regulations and economic policies in the following years.