Population. Although the United States remained a primarily rural nation, in the three decades before the Civil War the country's urban population increased by a remarkable 700 percent, from about 500,000 in 1830 to 3.8 million in 1860. Part of this growth represented an influx of immigrants from Europe, especially Ireland, but many of the new city dwellers were young people, primarily men, who came to the cities from outlying rural regions hoping to find employment as clerks, a generic title assigned to salaried retail or office workers. Because both clerks and their employers expected such positions to lead to larger financial rewards later, clerks in the early stages of their careers were paid very little and, if not housed by their employers, often lived in boardinghouses with other clerks. At a distance from their homes and families, with few resources, these young men were perceived to be...