Accounts of the early events of the computing industry--the Turing machine, the massive Colossus, the ENIAC computer--are well-told tales, and equally well known is the later emergence of Silicon Valley and the rise of the personal computer. Yet there is an extraordinary untold middle history--with deep roots in Minnesota. From the end of World War II through the 1970s, Minnesota was home to the first computing-centered industrial district in the world.