The Pony Express was a mail service delivering messages, newspapers, mail, and small packages from St. Joseph, Missouri, across the Great Plains, over the Rocky Mountains and the Sierra Nevada to Sacramento, California, by horseback, using a series of relay stations. During its 18 months of operation, it reduced the time for messages to travel between the Atlantic and Pacific coasts to about 10 days. From April 3, 1860, to October 1861, it became the West’s most direct means of east–west communication before the telegraph was established and was vital for tying the new state of California with the rest of the country.
The idea of a fast mail route to the Pacific coast was prompted largely by California’s newfound prominence and its rapidly growing population. After gold was discovered there in 1848, thousands of prospectors, investors and businessmen made their way to the California Republic. By 1850, California entered the Union as a free state. By 1860, the population had grown to 380,000. The demand for a faster way to get mail and other communications to and from this westernmost state became even greater as the American Civil War approached.
By utilizing a short route and using mounted riders rather than traditional stagecoaches, they proposed to establish a fast mail service between St. Joseph, Missouri, and Sacramento, California, with letters delivered in 10 days, a duration many said was impossible. The initial price was set at $5 per half-ounce, then $2.50, and by July 1861 to $1. The founders of the Pony Express hoped to win an exclusive government mail contract, but that did not come about.
Russell, Majors, and Waddell organized and put together the Pony Express in two months in the winter of 1860. The undertaking assembled 120 riders, 184 stations, 400 horses, and several hundred personnel during January and February 1860.
In 1860, there were about 157 Pony Express stations that were about 10 miles (16 km) apart along the Pony Express route. This was roughly the distance a horse could travel at a gallop before tiring. At each station stop the express rider would change to a fresh horse, taking only the mail pouch called a mochila (from the Spanish for pouch or backpack) with him.
As the Pony Express Mail service existed briefly in 1860 and 1861 there are consequently very few surviving examples of Pony Express mail. Also, contributing to the scarcity of surviving Pony Express mail is that the cost to send a 1/2 ounce letter was $5.00 at the beginning, a costly sum in those days and mostly unaffordable to the general public. By the end period of the Pony Express, the price had dropped to $1.00 per 1/2 ounce but even that was considered expensive ($26 in 2013 U.S. Dollars) just to mail one letter
In 1860, senior partner of ‘Russell, Majors, and Waddell.’, William Russell, one of the biggest investors in the Pony Express, used the 1860 presidential election as a way to promote the Pony Express and how fast it could deliver the U.S. Mail. Assuring that there would be fresh riders and horses along the entire Pony Express route, Russell, prior to the election, hired extra riders and ensured that fresh relay horses were available along the route. On November 7, 1860, a Pony Express rider departed Fort Kearny, Nebraska Territory (the end of the eastern telegraph line) with the election results. Riders sped along the route, over snow-covered trails and into Fort Churchill, Nevada Territory (the end of the western telegraph line). California’s newspapers received word of Lincoln’s election only seven days and 17 hours after the East Coast papers, an unrivaled feat at the time.
The Paiute War was a minor series of raids and ambushes initiated by the Paiute Indian tribe in Nevada, which resulted in the disruption of mail services of the Pony Express. It took place from May through June 1860, though sporadic violence continued for a period afterward. In the brief history that the Pony Express operated only once did the mail not go through. After completing eight weekly trips from both Sacramento and Saint Joseph, the Pony Express was forced to suspend mail services because of the outbreak of the Paiute Indian War in May 1860.
Approximately 6,000 Paiutes in Nevada had suffered during a winter of fierce blizzards that year. By spring, the whole tribe was ready to embark on a war, except for the Paiute chief named Numaga. For three days Numaga fasted and argued for peace. Meanwhile a raiding party attacked a Pony Express station called Williams Station, on the Carson River near present-day Lake Lahontan.
The identity of the first westbound rider to depart St. Joseph has been disputed, but currently most historians have narrowed it down to either Johnny Fry or Billy Richardson. Both Expressmen were hired at St. Joseph for A. E. Lewis’ Division which ran from St. Joseph to Seneca, Kansas, a distance of 80 miles (130 km). They covered at an average speed of 12 1⁄2 miles per hour (20.1 km/h), including all stops. Before the mail pouch was delivered to the first rider on April 3, 1860, time was taken out for ceremonies and several speeches. First, Mayor M. Jeff Thompson gave a brief speech on the significance of the event for St. Joseph. Then William H. Russell and Alexander Majors addressed the gala crowd about how the Pony Express was just a “precursor” to the construction of a transcontinental railroad. At the conclusion of all the speeches, approximately 7:15 p.m., Russell turned the mail pouch over to the first rider. A cannon fired, the large assembled crowd cheered, and the rider dashed to the landing at the foot of Jules Street where the ferry boat Denver, under a full head of steam, alerted by the signal cannon, waited to carry the horse and rider across the Missouri River to Elwood, Kansas Territory. On April 9 at 6:45 p.m., the first rider from the east reached Salt Lake City, Utah. Then, on April 12, the mail pouch reached Carson City, Nevada at 2:30 p.m. The riders raced over the Sierra Nevada Mountains, through Placerville, California and on to Sacramento. Around midnight on April 14, 1860, the first mail pouch was delivered via the Pony Express to San Francisco. Bringing with it was a letter of congratulations from President Buchanan to California Governor Downey along with other official government communications, newspapers from New York Chicago and St. Louis, along with other important mail to banks and commercial houses in San Francisco. In all, 85 pieces of mail were delivered on this first trip.
James Randall is credited as the first eastbound rider from the San Francisco Alta telegraph office since he was on the steamship Antelope to go to Sacramento. Mail for the Pony Express left San Francisco at 4:00 pm, carried by horse and rider to the waterfront, and then on by steamboat to Sacramento where it was picked up by the Pony Express rider. At 2:45 a.m., William (Sam) Hamilton was the first Pony Express rider to begin the journey from Sacramento. He rode all the way to Sportsman Hall Station where he gave his mochila filled with mail to Warren Upson. A California Registered Historical Landmark plaque at the site reads:
This was the site of Sportsman’s Hall, also known as the Twelve-Mile House. The hotel operated in the late 1850’s and 1860’s by John and James Blair. A stopping place for stages and teams of the Comstock, it became a relay station of the central overland Pony Express. Here, at 7:40 a.m., April 4, 1860, Pony rider William (Sam) Hamilton, riding in from Placerville, handed the Express mail to Warren Upson who, two minutes later, sped on his way eastward.
— Plaque at Sportsman Hall
An estimated 400 horses in total were used by the Pony Express to deliver the mail. Horses were selected for swiftness and endurance. On the east end of Pony Express route the horses were usually selected from U.S. Cavalry units. At the west end of the pony Express route in California, W.W. Finney purchased 100 head of short coupled stock called “California Horses”‘ while A.B. Miller purchased another 200 native ponies in and around the Great Salt Lake Valley. The horses were ridden quickly between stations, an average distance of 15 miles (24 km), and then were relieved and a fresh horse would be exchanged for the one that just arrived from its strenuous run.
During his route of 80 to 100 miles (130 to 160 km), a Pony Express rider would change horses 8 to 10 times. The horses were ridden at a fast trot, canter or gallop, around 10 to 15 miles per hour (16 to 24 km/h) and at times they were driven to full gallop at speeds up to 25 miles per hour (40 km/h). Horses of the Pony Express were purchased in Missouri, Iowa, California, and some western U.S. territories.
The various types of horse ridden by riders of the Pony Express included Morgans and thoroughbreds which were often used on the eastern end of the trail. Mustangs were often used on the western (more rugged) end of the mail route. 
During its brief time in operation, the Pony Express delivered approximately 35,000 letters between St. Joseph, Missouri, and Sacramento, California. Although the Pony Express proved that the central/northern mail route was viable, Russell, Majors and Waddell did not get the contract to deliver mail over the route. The contract was instead awarded to Jeremy Dehut in March 1861, who had taken over the southern Congressionally favored Butterfield Overland Mail Stage Line. The so-called ‘Stagecoach King’, Ben Holladay, acquired the Russell, Majors and Waddell stations for his stagecoaches.
Shortly after the contract was awarded, the start of the American Civil War caused the stage line to cease operation. From March 1861, the Pony Express ran mail only between Salt Lake City and Sacramento. The Pony Express announced its closure on October 26, 1861, two days after the transcontinental telegraph reached Salt Lake City and connected Omaha, Nebraska and Sacramento, California. Other telegraph lines connected points along the line and other cities on the east and west coasts.
The Pony Express grossed $90,000 and lost $200,000.