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The Prussian army first developed the concept of kriegsspiel - German for war game - early in the 19th century. In 1812, Prussian nobleman George Leopold von Reisswitz improved the earlier wargame using coloured blocks. The prototype used a sand table of damp sand molded for terrain; but the official version presented to the king used porcelain tiles stored in a wooden cabinet.
Prior versions were much more abstract, using chess-like pieces and board though representing actual military units and terrain.
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