Actually it refers to the scratch line of a foot race, the starting line. Some racers were allowed to start a little ahead as a handicap. So starting from scra

Actually it refers to the scratch line of a foot race, the starting line. Some racers were allowed to start a little ahead as a handicap. So starting from scratch meant that you started at the beginning. Made from scratch came along later, picking up from the usage of this word. What I'd like to know is where "Old Scratch", aka the devil came from.