Nitro emerged as a boom town during America's mobilization for World War I. Its name was chosen by Dr. Arthur Swanson, a technical advisor on the Ordinance Department team, from the chemical term Nitro-Cellulose, the type of gunpowder to be produced there. Ground was broken on December 23, 1917, at the site of the present Nitro City Park to build the first twenty-seven two-hundred-bed barracks, and almost immediately thousands of workers and trainloads of materials and supplies poured into the muddy pasture along the river. Government records showed that more than 110,000 people were on the payroll during the eleven months required to build the plant. By the time the war ended on November 11, 1918, the vast manufacturing complex, officially called Explosive Plant C, was already operating and could produce 350 tons of smokeless gunpowder each day. The town was 90 percent complete and housed 23,951 people, with modern housing and utilities, an independent school system, full-time police and fire protection, a hospital, and recreational facilities. By 1921, many wartime holdovers were making their homes there, and young couples relied on friends and neighbors for fellowship, shared interests, and help in times of need while forming clubs and civic organizations that helped shape the town's growth, development, and enduring community spirit.