Welshmen and Scotsmen provoked their stronger neighbors of England in the late thirteenth century into wars that almost filled the reign of Edward I. Whether in keeping with “Manifest Destiny” or not, King Edward accepted the provocation of the Welsh and sent his troops into their land in an attempt to subjugate them; by a workmanlike series of campaigns he conquered and pacified them between 1277 and 1294. Then began an almost unbroken period of war against the Scots, a period lasting well beyond Edward's own death in 1307. By their persistence and by their tactics the Scots forced Edward and his people to a major effort, one that made every Englishman aware of his obligation, whether to fight, to feed the fighters, or to support the fighters with works.
For medieval soldiers, like their modern descendants, war was mostly a matter of working and waiting. Battles punctuated the wars, then as now, and at these times the combat troops spent their strength. During the long stretches between battles, however, support elements continued to supply the troops and put them into position to fight. The men in the armies of Edward I who kept the war going in this way and kept going themselves were the auxiliaries: the ditchers, woodcutters, smiths, carpenters, paymasters, provisioners, and the engineers. Important as they were in medieval warfare, the engineers have received little credit for it. Their work, bridging, building fortifications, and operating artillery, rarely rates a description in a chronicle and they receive little notice in secondary works.