I'm a big fan of Mark Twain, born Samuel Clemens. I read The Adventures of Tom Sawyer several times, and The Adventures of Huckleberry Finn three or so times. When I became a fan of Finnegans Wake, I discovered James Joyce expressing appreciation of Twain's work in that book.
I'm also a fan of Sid Fleischman. Our kids enjoyed his McBroom stories that we read to them. Escape!: The Story of the Great Houdini is an excellent biography. So I was pretty sure I'd like The Trouble Begins at 8: A Life of Mark Twain in the Wild, Wild West.
I was right.
Now if you haven't read Tom Sawyer or Huckleberry Finn, I'd say wait. Don't read the biography until you've read at least one of those.
Unless, of course, you feel like reading a good biography now.
Twain was an interesting guy. He piloted steamships up and down the Mississippi, earning then what the Vice President of the United Sates earned.
He was a printer, a journalist, he prospected for gold, did a good bit of traveling, and some very humorous writing.
In this book, Fleischman focuses on Twain's early life, when he was known as Sam (or Sammy) Clemens. It's a great story.
If you like it, I want to recommend another short biography of a fascinating character - Charles Dickens, by Jane Smiley.