Historians debate whether there was a late medieval “military revolution” during the fourteenth century, as states continued to develop, alongside big economic and social change. In Europe, a new regional power emerged in Poland-Lithuania. In the Muslim world, the Ottoman Turks rapidly became a potent force and brought Islam into the Balkans. Russia shook the rule of the Golden Horde for the first time under the leadership of a new city state, Muscovy, while the Mongol Yuan dynasty in China was overthrown and native rule restored with the Ming.

Conflicts in Iberia in the 1360s were part of the wider struggle known as the Hundred Years War. The whole of western Europe became embroiled as direct or proxy participants, and warriors who found themselves temporarily without employers began to market their skills as condottieri (contracted soldiers) to the Italian cities. In the course of this century we will note the first uses of gunpowder artillery and consider its impact.

England under Edward II

England was the instigator of the trouble. The troubled reign of Edward II was marked by military disaster in Scotland, and civil war. The king had repeated problems at home. In 1316, for example, riots in the city of Bristol were sufficiently threatening to require a naval blockade, and an attack on the townspeople from the castle with stone throwers, which in a few days demolished houses and stretches of the wall. In 1321 the king was engaged in full-scale civil war with many of his leading barons. The latter stormed through the marches of Wales seeking to capture the base of Edward's favourite, Hugh Despenser, who had been gifted the vast lordships of Glamorgan. The small castle of St. Briavels in the forest of Dean, a royal centre for the manufacture of such munitions as crossbow bolts, powerfully provided with a large modern gatehouse, and the older castle at Newport both fell easily, as their custodians gave them up (May 1321). In an inquest, it was noted that the earl had lost the castles of Newport, Cardiff, Caerphilly, Llanblethian, Kenfig, Neath, Dryslwyn and Dinefwr among others, and amongst the equipment removed by the captors were engines and springalds.