The Medieval era was a period of huge variety and invention in the field of siege warfare. Before the use of cannon and other gun-powder artillery, siege engines relied on assorted sources of power from torsion 'energy storage' systems to man-power, counter-balances and others. This book reveals how the combining of technological traditions from the Graeco-Roman world, Persia, India and above all China made a massive contribution to the development of siege techniques. Medieval military engineering was equally inventive in terms of mining, counter-mining, the breaking of walls, the use of noxious and chemical fumes and the use of fire-weapons.