Which war was fought to determine whether the United States would remain unified or divide into two nations?

The Civil War was fought from 1861 to 1865 and primarily centered on the vital issue of states' rights and slavery, which created a significant divide between the North and the South. The Confederate states sought to secede from the Union, leading to an armed conflict to determine the future of the nation. The war ultimately aimed to decide whether the United States would remain a single, unified nation or split into separate, independent entities. The outcome of the Civil War reaffirmed the federal government's authority and resulted in the preservation of the Union, making it a crucial turning point in American history regarding national unity and civil rights. The significance of this conflict lies in its lasting impact on the country's governance and social structure, illustrating the struggle over fundamental issues that define the nation's identity.