Nazi System 360/370 book...

That's exactly what happened. I had the same reaction as you: why would IBM have to buy a German Hollerith machine company when the inventor himself was already part of the company that would become IBM? On the face of it, it sounds like a big circle. I guess it was because the Germans developed a better hardware implementation of the machines and the Americans wanted the business in German and the rest of Europe, which Dehomag had bought the rights to. Wikipedia has a little bit on it, not much, and I found an interesting article on the IBM site about a restoration of one of the very early machines from Dehomag. http://www.ibm.com/ibm/greateribm/connections/connections_article26.shtml I don't know if you've ever seen an IBM check sorter, but they are amazing pieces of engineering. I can't see the picture too well in the IBM article but they do mention the check sorters are related to these early machines.