Samuel Langhorne Clemens—better known by his pen name Mark Twain—was born in Florida, Missouri, on November 30, 1835, and grew up in Hannibal, Missouri. Twain, who was the sixth of seven children, moved with his family in 1839 to the frontier town of Hannibal since it offered better financial prospects for Twain's father, John Marshall Clemens. However, during and after his early childhood, Twain spent many summers at his uncle John Quarles's farm in Florida. The farmhouse, which had as many as 30 enslaved people on its premises, was a rural paradise for Twain; he would later use these experiences, including the friendships he developed with enslaved people, in his most important books.
As a young boy Twain was sickly and was cared for by his mother, Jane Lampton Clemens. She was a fun-loving, tenderhearted woman whose love of storytelling later inspired her son to write. Unlike his wife, John was a serious person who felt great stress over the family's financial situation. He was, however, a dreamer and believed one day he would be wealthy. When John died in 1847, the family became destitute, and Twain's boyhood was over.
At age 13 Twain left school to become a printer's apprentice for a local newspaper owned by his brother Orion. Twain began to contribute some sketches and articles despite friction with his older brother. When Twain turned 17 he left Hannibal and went to several large cities, including Philadelphia and New York. He continued to work for newspapers, operating as a printer in Cincinnati, Ohio, and writing a series of letters under the pen name "Thomas Jefferson Snodgrass."
In 1857 another travel plan—this time to South America—was abandoned for an opportunity to learn to pilot a steamboat on the Mississippi River. He became a licensed pilot in 1859. He loved the job, and it impacted his writing greatly, inspiring many articles later published in The Atlantic Monthly and key books such as Life on the Mississippi (1883) and The Adventures of Huckleberry Finn (1884). In 1863 Twain wrote his first piece under the pseudonym "Mark Twain." There are a number of stories—some potentially untrue—about the origin of Twain's most famous pen name, including his own claim that he stole the name from a senior riverboat captain who used to sign his bland descriptions of the Mississippi River under the name "Mark Twain." However, it is most likely that Twain adopted the name from a steamboat slang term meaning 12 feet of water.
When the Civil War put an end to commercial steamboat traffic, Twain made his way out west and worked for a number of newspapers. During this time in the West, Twain met the influential author Bret Harte. He also first found publishing success in 1865 with a short story called "Jim Smiley and His Jumping Frog," which was printed in newspapers across the country. The story would eventually appear in Twain's first published book, The Celebrated Jumping Frog of Calaveras County, and Other Sketches (1867). His first of many travel books, The Innocents Abroad, was published in 1869 and detailed his trip to Europe and the Holy Land on the steamship Quaker City. The book was a major success, though the foundation for his fame had already been laid by the many letters he had published in newspapers during his five-month voyage on the Quaker City.
In 1870 Twain married Olivia Langdon and settled in Buffalo, New York. Two years later he commissioned the construction of a mansion in Hartford, Connecticut, where he resided until 1891.
During the 1870s Twain continued to write and give lectures across the country. Over the next 20 years Twain wrote some of his most famous books during summers spent at Quarry Farm, located in Elmira, New York. The farm belonged to Olivia's sister following the death of Twain's father-in-law, Jervis Langdon. Twain published another travel book, Roughing It (1872), before turning to novels.
Twain's works were often sold by subscription via door-to-door sales agents, guaranteeing an audience and a healthy profit before a book was even published. His best known works were those inspired by his boyhood along the Mississippi: The Adventures of Tom Sawyer (1876) and The Adventures of Huckleberry Finn (1884). He followed those successes with many more books, including the biting satirical work A Connecticut Yankee in King Arthur's Court (1889) and the antislavery novel The Tragedy of Pudd'nhead Wilson (1894). He continued to tour the country and abroad, having become famous not only as a writer but as an entertaining lecturer.
For all of his writing accomplishments, however, Twain was not a wise businessman. In his later years, he suffered financial difficulties, which ultimately led him to declare bankruptcy and to sell his Hartford home. Henry Huttleston Rogers of the Standard Oil Company took over managing Twain's finances in 1893 and got him back onto solid ground. When Twain returned to the United States in 1900, he made good on his debts and attained increased public acclaim as a result.
Twain suffered personal tragedies as well during the 1890s and early 1900s, losing first one of his daughters and then his wife. The tone of his writings shifted toward bitterness, though he retained his sense of humor, as witnessed in The Man That Corrupted Hadleyburg, and Other Stories and Essays (1900), as well as the posthumous Mark Twain's Mysterious Stranger Manuscripts (1969). His bitterness also comes through in his autobiography, which he began to dictate in 1906. (Twain published his autobiography in parts in 1906–07, but a complete three-volume edition was published between 2010 and 2015.) Twain died on April 21, 1910.