Fortifications are militaryconstructions designed for defensivewarfare. They have been used for many thousands of years, in a variety of increasingly complex designs. The practice of improving an area's defense is also known as "fortification". Many military installations are known as forts, although they are not always "fortified".
... April 7 - Ralph Bunche[?], diplomat, winner of the Nobel Peace Prize
April 16 - Fifi D'Orsay, actress (+ 1983)
April 22 - Robert Oppenheimer, physicist (+ 1967)
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