Milan was a centre for the manufacture of arms and armour, and soon after Leonardo’s arrival in the city he began to sketch designs for weapons. The recent introduction to Europe of gunpowder was rapidly changing the nature of warfare, and Leonardo’s designs show both the old type of weapon, such as lances and chariots, and the new – guns, cannon and mortars.

It is unlikely that any of these designs was realised, or even intended for manufacture, and they may have been intended instead for an illustrated treatise on warfare.