European Counterweight Trebuchet

Timeline

1. c. 1230–1240Northern France · FranceIn the first half of the 13th century Western European craftsmen improved the trebuchet's pivot and counterweight box, replacing large manpower crews with stone or lead weights, greatly increasing throwing efficiency and maximum projectile weight.
2. 1241–1250Iberian Peninsula · IberiaBetween 1241 and 1250 counterweight trebuchets were frequently deployed in the Iberian Reconquista and in attacks and defenses of Crusader coastal fortresses, battering Muslim castle walls in coordination with scaling ladders and mining operations.
3. 1245–1250England · EnglandBy around 1250 the royal arsenals of England and France could independently build medium-sized counterweight trebuchets; specifications and operating manuals spread among noble siege forces, laying the groundwork for Edward I's large-scale sieges.