The Missouri Pacific Railroad was one of the first railroads in the United States west of the Mississippi River.
On July 4, 1851, at St. Louis, Missouri, ground-breaking for the Pacific Railroad marked the beginning of what would would become the Missouri Pacific Railroad. The first section of track was completed in 1852. In 1872, the Pacific Railroad was reorganized as the Missouri Pacific Railway by new investors after a railroad debt crisis.
By the 1980s the system would own 11,469 miles of rail line over 11 states bounded by Chicago to the east, Pueblo, Colorado, in the west, north to Omaha, south to the U.S.-Mexico border in Laredo, Texas, and southeast along the Gulf seaports of Louisiana. MoPac operated a fleet of over 1,500 diesel locomotives, most all purchased within the previous 10 years. The company merged with Union Pacific in 1982.