Maruder

Maruder, a tramp, a robber) in the Middle Ages and in modern times until the nineteenth century, a civilian behind the army with the intention of conquering the goods brought about by the war. They dealt with the trespassing on the battlefield, as well as the hoarding or hoarding of merchants in the armistice camps (see markietan). In the eighteenth and nineteenth centuries marauders were also called soldiers at the rear of the column of troops, both unmarried troops and deliberately left behind for robbery, rape, or looting.

From marrying, you have to distinguish between desertion and abandonment to evade military service, although the border may be fluid.

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