How Samuel Clemens became Mark Twain

Rob Velella at The American Literary Blog provides more details of the birth of the pen name "Mark Twain:"

A man named Samuel L. Clemens traveled west with his brother, across the Great Plains, over the Rocky Mountains, and stopping in the territory of Nevada, where he got a job as a miner. That role didn't work out for him and, instead, he turned to the local newspaper, the Territorial Enterprise.

He achieved some notoriety there, later writing to his mother somewhat tongue-in-cheek as having "the widest reputation" possible on the frontier. He noted, "If I were not naturally a lazy, idle, good-for-nothing vagabond," he might even make money off it. "And I am proud to say I am the most conceited ass in the Territory." Such was Clemens's humor.

In fact, some of his writing for the Enterprise was humor rather than pure journalism. Such was the case for its February 3, 1863 issue, when one of those articles by Clemens was signed, inexplicably, with a pseudonym. Though Samuel Clemens was 28 years old, some call this the birthday of "Mark Twain."

The name comes from the call made by leadsmen aboard riverboats (a role Clemens held at one point), and most scholars agree this was the intended reference. However, in 1874, Clemens wrote a letter offering his own explanation. He claims that he borrowed the name from a senior boat pilot named Isaiah Sellers, who himself used the name when he wrote for the Picayune, a newspaper in New Orleans. He stopped using the name when Clemens made fun of him for it. Sellers died in 1863 and, perhaps to make amends, Clemens took it over, noting that Sellers didn't need it anymore. In fact, the story doesn't check out; Sellers was still very much alive when Clemens adopted the name "Mark Twain," and no articles under that name existed in the New Orleans paper.

Another story claims that Clemens used to order two drinks at once while at the taverns out west. He would ask that both ("twain") be "marked" on his bar tab. In theory, then, he would go to the bar, hold up two fingers, and ask the bartender to "mark twain."