After the 1812 War Victory, The United States of America emerged as a strong nation that can defend itself. On the other hand, U.S will turn to its domestic affairs such as Expansion.

This period was marked by dramatic territorial growth, escalating sectional tensions, and the ultimate breakdown of national unity in the Civil War. Following the devastation, the Reconstruction era sought to rebuild the South and redefine freedom and citizenship in the United States—an effort filled with both bold progress and deep resistance.

This chapter explores the transformative period following Reconstruction, marked by rapid industrialization, urban growth, and technological innovation. The rise of powerful industrial tycoons reshaped the economy, while harsh labor conditions gave birth to new labor movements. Simultaneously, America expanded its global presence through imperialist ventures, asserting influence over territories abroad. These developments laid the foundation for the modern United States and reflected a growing tension between democratic ideals and economic power.