On the face of it, the 1450s seem quite simple: growing internal violence and a steady descent into civil war concluded by the deposition of Henry VI and the accession of the Yorkist Edward IV in 1461. But closer examination reveals rather less coherence. The seeds of confrontation were already there in 1450, and we must therefore consider why they took so long to germinate. Then, although the Wars of the Roses are normally thought to have started with the first battle of St Albans in 1455, there followed four years of uneasy truce. Arguably the Wars did not really begin until late 1459, with the encounter at Blore Heath. Indeed, during the 1450s, politics seem to have progressively less coherence. More baffling still is the mode of deposition. On both previous occasions, 1327 and 1399, the king's military power had just melted away, exemplifying royal dependence on landowners' support for military security. In this instance, however, Edward IV had to make good his claim to the throne in battle and even then his position remained under threat until the Lancastrians were finally disposed of in 1471. All these facts require explanation and all of them have their roots in the events of 1450–5.

The period from 1450 until the first battle of St Albans in May 1455 was dominated by the deteriorating relations between the dukes of York and Somerset.