The subject of this thesis is the social significance of knighthood in England during the reign of Edward I. The introduction outlines the process whereby knightly rank became associated with landed wealth. Evidence discussed in the second chapter points to the existence of many knights. The personal relationships between them indicate a defined social group. Next it is argued that the failure from the late 13th century of many landholders to take knighthood was prompted by financial considerations but the group retained its integrity. The fourth and fifth chapters investigate the nature of the knights ' lordship and reveal great variations in their social and economic power. The following chapter shows that inheritance underpinned the changing composition of the knightly group into which freemen might prosper. It is then suggested that territorial and family solidarities were more instrumental in determining alliances between knights and greater landholders than feudal tenurial ties. It is next shown that military and administrative service occasionally overlapped but those aspects of service were crystallizing respectively around the retinues of the magnates and the lesser knights active in the counties. The conclusion suggests that the cult of knighthood legitimized the social position of all knights.