Mark Twains first important work was The Celebrated Jumping Frog of Calaveras County next Twain was commissioned by the Sacramento Union to write letters about his travel experiences for publication in the newspaper, his first of which was to ride the steamer Ajax in its maiden voyage to Hawaii, referred to at the time as the Sandwich Islands. Then he wrote The Innocents Abroad or The New Pilgrims' Progress. Roughing It, The Gilded Age: A Tale of Today,Old Times on the Mississippi, Life on the Mississippi, The Adventures of Tom Sawyer was next. Then came A Tramp Abroad, Andventures of Huckleberry Finn (The Great American Novel)A Connecticut Yankee in King Arthur's Court,Pudd'nhead Wilson, Personal Recollections of Joan of Arc,The Mysterious Stranger and Twain's last work was his autobiography. Hope this helped you out and sorry it was so long.