The Civil War lasted four years and was the deadliest war in American history with over 620,000 casualties. The 25 states forming the Union fought against the rebelling 11 Confederate states. Although the Confederacy fought mostly on home soil and had better generals, the Union had several advantages that led to its eventual victory.

Population

Before the Civil War began, the Union had 21.5 million people, while the Confederate states had only 9 million. Three million residents of the Confederate states were slaves who were not allowed to fight, which further lowered the pool of men eligible for the Confederate Army. The North's greater population allowed surplus men to continue working in industry, while the South needed all its eligible men in the field.

Industry

The United States was in a period of industrial growth in the 1800s. The Northern states had numerous factories and industrial organizations, while the South depended on agriculture. Before the Civil War began, the North made over 90 percent of the guns, textiles, pig iron and boots in the country. In fact, when the war began the South had no rifle factories. Many of its men went to battle with their own weapons while the Northern soldiers were supplied with the latest in rifle technology. The Union used its vast industrial resources to continually produce military supplies and the Confederacy could not keep up with them.

Navy

The Union had a strong navy that it used to blockade Confederate ports. This prevented the South from receiving imports from overseas. In total, the Union Navy started the war with 90 naval vessels while the Confederate Navy had only 32. Although the South had some blockade runner ships that could shuttle supplies in and out of certain ports, the Union blockade was nearly impossible to pass two years after the war began. This shut off the Confederate Army's ability to purchase much needed supplies from other lands.

Transportation Network

Because of its greater industrial strength, the North had a large transportation network. In the prewar years, the Union had 21,700 miles of railroad tracks, while the South had just 9,000 miles. The Union's advanced transportation system allowed it to ship soldiers and war supplies from cities to the war front. In contrast, even though the South produced enough food to feed its armies, the limited railroad system prevented much food from getting to the front.

Support of Other Nations

The Confederate States of America tried to get France and Great Britain to recognize it as a legitimate government, but they failed to do so. Officially, neither country would support a government that supported slavery. Other countries did recognize the United States government, giving it a significant diplomatic and financial advantage. The Union received loans and trade concessions from foreign nations. In contrast, the Confederacy was cut off by the Union blockade and was not aided by foreign governments.