The article on wordorigins.org contains more information, including this quote: Use of southpaw to mean the left hand goes back all the way to 1813, long befor

The article on wordorigins.org contains more information, including this quote: Use of southpaw to mean the left hand goes back all the way to 1813, long before baseball, as we know it today, existed. It’s used in a letter appearing in the Philadelphia newspaper The Tickler on 30 June of that year: “Luk here mon, and convince yourself,” said he, holding up the Tickler, in the right paw, between the ceiling and the floor, and with the south paw pointing to the “bow, vow, vow.” (Source - http://www.wordorigins.org/index.php/site/comments/southpaw/ http://www.wordorigins.org/index.php/site/comments/southpaw/)