This series contains essoin rolls of the Chester County Court running, with gaps, from 1342 to 1507. Essoins were claims of allowable excuses, which included illness or being engaged in the king's service, for non-appearance in a court of common law to answer an opponent suing using various kinds of writ, and were subject to detailed rules. As in other series, the rolls contain, under sessional headings, brief entries of the name of the person for whom the essoin was caste, the name of his or her opponent, the kind of plea, and the essoiner who cast it.
In the later rolls the essoiner was always fictitious; the name used was John Pye; earlier, in the late fourteenth century, Adam Cat, Prat, Hat, Lat, Cak, Halt, Malt and other variants were prominent, while in the mid fifteenth century names like Fox, Hare, Pope, Ros, More and Fray occur.
The rolls do not duplicate information in the plea rolls, which contain no essoin sections; they only contain entries bginning 'essoin' when someone who had failed to appear on the date to which he or she had been essoined.