Adaptation of Fortifications in the Gunpowder Age

Timeline

1. c. 1400–1440Western European battlefields (Hundred Years' War between England and France, etc.) · FranceSiege artillery in conflicts such as the Hundred Years' War gradually proved its power to destroy medieval high stone walls; defenders began experimenting with lowering parapets, filling in tower bases, and thickening wall foundations to absorb cannon fire.
2. 1453–1460Constantinople (Istanbul) · MarmaraOttoman giant bronze cannons blasted down the Theodosian Walls, making European rulers broadly aware that traditional castle designs could no longer withstand concentrated bombardment; old fortresses were urgently reinforced and cannon emplacements rearranged.
3. c. 1445–1500Italian Peninsula · ItalyItalian city-states, driven by Renaissance military engineers, experimented with low, flat earth-and-stone bastions, triangular salients, and interlocking fields of fire, forming the prototype of the trace italienne and retroactively modifying existing medieval castles.