The grid also forced the terrain into unnatural forms, such as rivers that flowed in straight lines and bent at right angles. This lack of realism meant that no army took these wargames seriously. Kriegsspiel (1824) In 1824, a Prussian army officer named Georg Heinrich Rudolf Johann von Reisswitz presented to the Prussian General Staff a highly realistic wargame that he and his father had developed over the years. Instead of a chess-like grid, this game was played on accurate paper maps of the kind the Prussian army used. This allowed the game to model terrain naturally and simulate battles in real locations. The pieces could be moved across the map in a free-form manner, subject to terrain obstacles. The pieces, each of which represented some kind of army unit (an infantry battalion, a cavalry squadron, etc.), were little rectangular blocks made of lead. The pieces were painted either red or blue to indicate the faction it belonged to. The blue pieces were used to represent the Prussian army and red was used to represent some foreign enemy—since then it has been the convention in military wargaming to use blue to represent the faction to which the players actually belong to. The game used dice to add a degree of randomness to combat. The scale of the map was 1:8000 and the pieces were made to the same proportions as the units they represented, such that each piece occupied the same relative space on the map as the corresponding unit did on the battlefield. The game modeled the capabilities of the units realistically using data gathered by the Prussian army during the Napoleonic Wars. Reisswitz's manual provided tables that listed how far each unit type could move in a round according to the terrain it was crossing and whether it was marching, running, galloping, etc.; and accordingly the umpire used a ruler to move the pieces across the map. The game used dice to determine combat results and inflicted casualties, and the casualties inflicted by firearms and artillery decreased over distance. Unlike chess pieces, units in Reisswitz's game could suffer partial losses before being defeated, which were tracked on a sheet of paper (recreational gamers might call this "hitpoint tracking"). The game also had some rules that modeled morale and exhaustion. Reisswitz's game also used an umpire. The players did not directly control the pieces on the game map. Rather,