What was a significant factor regarding the outcome of the Civil War?

The significant factor regarding the outcome of the Civil War is the increase in American deaths compared to any other war. The Civil War resulted in an estimated 620,000 to 750,000 military deaths, which was a staggering number and accounted for a higher percentage of the population at that time than any other American conflict. This unprecedented loss of life had profound implications on American society, affecting families, communities, and the nation's approach to warfare. The scale of casualties also highlighted the war's intensity and the profound divisions within the country, ultimately leading to significant political and social changes in the aftermath of the conflict.

In contrast, while the formation of new territories is historically relevant, it did not directly influence the outcome of the Civil War itself; rather, it was a consequence of the war's aftermath. The establishment of an independent government in the South reflects the Confederacy's initial aspiration, yet it did not last long nor achieve enduring recognition or stability. Lastly, the importation of slaves from Africa is not directly connected to the Civil War's outcome, as by that time, the transatlantic slave trade had been outlawed in the United States. Thus, it's the staggering human cost that fundamentally shaped the war's legacy and its impact on the nation.