Konrad Zuse did a lot of development work in Germany in the '30s. He built electromechanical machines that ran programs punched into used 35mm film. Rumor has it that the Z1 ran its first program sometime around 1935. I've heard it was unable to execute conditional branches, which was the excuse used (at the time I heard the rumor) for not recognizing it as the first computer.
Since history is written by the victors, Zuse is often overlooked.
The original Z1 was destroyed during World War II. There's a rebuilt Z1 on display in Berlin. The Computer History Museum has a portion of a Z3 on display.
After the war, the Zuse company continued to build computers. The Computer History Museum has a portion of a Z23 on display.
| Zuse Z23 | ||
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| X | ||
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| U | ||