Mark Twain was born Samuel Langhorne Clemens on November 30, 1835, in the village of Florida, Missouri. When his father died in 1847, Clemens—who was only twelve years old at the time—was sent to be a printer's apprentice. While his early life was spent in Missouri, Clemens left home as a young man and was a traveler for the rest of his life, often taking on odd jobs, submitting various writings for publication, and assuming other odd jobs to fund his adventures.

After working as a riverboat pilot and spending some time in the South, where he was a Confederate soldier for two weeks, Clemens moved to the developing American West. He first gained popularity in small towns as a journalist using the pseudonym Mark Twain, a nautical term from his riverboat pilot days. He later became known as a travel writer, humorist, and lecturer.

Clemens married...