The action of covenant before the reign of Edward III is a subject of considerable mystery. By the time that the Year Books come to the fore in the last decade of the thirteenth century, it has become a relatively scarce form of action in the royal courts, and consequently our sources of information are fairly scanty; in addition, by this time, the restrictions which limited the potential of covenant as a general contractual remedy are already firmly in evidence, with the result that the development of these restrictions is not easily visible. There is, though, a considerable amount of additional material in the rolls of the Justices in Eyre in the reign of Edward I, and in some of the multifarious tracts on pleading which proliferated in the later years of the thirteenth century and which have remained for the most part in manuscripts which have not been systematically examined by legal historians.