 Immediately after his marriage in 1870 to Frances Macbeth, Glessner relocated to Chicago where he opened a branch office.In 1902, the firm and four others, including firms controlled by J. P. Morgan, Cyrus McCormick, and James Deering, merged to form International Harvester (now known as Navistar International Corporation), which became the fourth largest corporation in the country.Glessner was appointed vice president and continued in that capacity for many years.