The epic story of the construction of the first railroad to run from coast to coast began in the 1840s, with the acquisition by the United States of vast new western lands as a result of the war with Mexico. But the individual states and regions argued among themselves about which route was the most desirable, causing a deadlock in Congress which lasted throughout the 1850s.
By June 1861, a railroad was a necessity for the over 300,000 inhabitants of California. The moneyed interests of the state decided to act on their own, and formed the Central Pacific Railroad Company in San Francisco. These same interests were able to push through the transcontinental railroad bill in Congress on June 20, 1862. With the Southern states out of the Union, a route along the 42nd parallel was chosen for the railroad, running from Omaha, Nebraska along the Platte River and through Wyoming, Colorado, Utah and Nevada to San Francisco. The Central Pacific Railroad was chosen as the company to build over the Sierras. Congress gave them 10 to 20 square miles of public land plus up to $48,000 in loans for every mile they completed. Congress incorporated the Union Pacific Railroad Company to build west from Omaha, and gave them a right-of-way of 400 ft. and 20 sections of land (12,800 acres) for each mile of road in existing states, and 40 sections (25,600 acres) for each mile of road in U.S. Territories.
Ground was broken for the Union Pacific at Omaha on December 2, 1863 and the Central Pacific broke ground on January 8, 1863 at Sacramento, California and many long years of work commenced. Finally on May 10, 1869 with the telegrapher's message, "1, 2, 3, Done!" the golden spike had been driven home at Promontory, Utah, completing Americas' first transcontinental railroad, the Union Pacific/Central Pacific.
For many people the railroads themselves became important employers and economic factors. Many end-of-rail towns, such as Cheyenne, Wyoming, became important rail junctions where locomotives were serviced, cars could be maintained, freight classification yards operated, and crews were changed, and travelers rested and ate. Other places grew from small towns into great cities as a result of the railroads. Denver, for example, had been a mining town and probably would have become a ghost town after the ore had played out if not for the entry of the rails. Soon after the arrival of the railroad, warehouses, stores and factories were built, and Denver became the great city of the Rocky Mountains.
Of course there is another side of the story to the construction of the railroads. American Indians, who contrary to Hollywood's version had looked upon the early wagon trains with more curiosity than maliciousness, now found their entire lifestyle threatened by the "iron horse." Often passengers shot buffalo from moving trains just for sport. The rails scarred Indian hunting grounds. Within a little more than a decade, Indians were relocated on reservations, and their once vast hunting grounds became farms, towns, ranches and cities.
By 1890 the United States Census Bureau determined that there was no longer a western frontier, since all parts of the west had been explored and settled. By 1900 there were 260,000 miles of track in the U.S. Gauges and time zones had been standardized, air brakes and automatic couplers installed, locomotives improved, rails strengthened, and Pullman and dining cars added. Not only were there regular railroad lines, but also interurban transit between cities and trolley lines, elevated railroads and subways within cities. America was a nation on rails everywhere one looked by the end of the 19th century, a century of steam and rails which united West and East more quickly and efficiently than any other single factor.